NSU Genetics

A woman whose hemoglobin S levels are less than 1% has a brother with sickle cell disease, and both parents have been diagnosed as carriers for the disorder. She asks what her risks are of having a child with sickle cell disease. What is the best response? A. "Because you do not have the trait, you cannot have a child with sickle cell disease regardless of your partner's sickle cell status." B. "Because both your parents have the trait, it is possible for you to have a child with sickle cell disease if your partner actually has the disease." C. "Because your brother actually has sickle cell disease, the risk for your children having sickle cell disease is 50% with each pregnancy." D. "Because you are a woman, your daughters will each have a 50% risk for having the disease, and all of your sons will be carriers of the trait."

A. "Because you do not have the trait, you cannot have a child with sickle cell disease regardless of your partner's sickle cell status."

What is the best definition of the term compound heterozygous? A. A person who has two different mutated alleles for an autosomal-recessive disorder B. A person whose expression of an autosomal-recessive disorder is modified by silencing of one allele C. A person who expresses a genetic disorder having different mutations on two nonhomologous chromosomes D. A person having a complex disorder in which there is unequal influence of genetic and environmental contributions

A. A person who has two different mutated alleles for an autosomal-recessive disorder

Which condition in a newborn should be described as a deformation if it is the only abnormal finding? A. A unilateral clubfoot B. A sealed (imperforate) anus C. The absence of a thyroid gland D. The presence of six toes on each foot

A. A unilateral clubfoot

Which statement or factor is a criterion for autosomal-recessive transmission of a single-gene trait? A. About 25% of the members of a large kindred with an autosomal-recessive trait will express the trait B. There is no carrier status; if the allele for the trait is present, it is expressed, although the degree of expression can be variable C. Individuals who are heterozygous for an autosomal-recessive trait have minimal risk for transmitting the allele to their offspring D. The degree of expression of an autosomal-recessive trait or disorder in a homozygous individual is directly related to the penetrance of the trait

A. About 25% of the members of a large kindred with an autosomal-recessive trait will express the trait

Which observations in a pedigree indicate a probable autosomal-dominant (AD) trait transmission? A. Affected males and females appear in every generation. B. The pedigree shows only one affected individual. C. The trait appears to "skip" generations. D. Only males are affected.

A. Affected males and females appear in every generation.

What mechanism results in the malformation of cleft lip? A. An abnormal developmental process B. An abnormal organization of cells C. A mechanical process D. The breakdown of an originally normal developmental process

A. An abnormal developmental process

Couples from which ethnic group would derive the greatest benefit from genetic testing for Tay-Sachs disease? A. Ashkenazi Jews B. Asian Americans C. French Canadians from Quebec D. Individuals of Mediterranean descent

A. Ashkenazi Jews

What is the most important action to take when assessing an infant for possible dysmorphic features? A. Assess the phenotypes of first-degree relatives. B. Count the number of minor anomalies present. C. Use an atlas that includes globally diverse populations. D. Determine whether an identified dysmorphic feature is a malformation or a deformation.

A. Assess the phenotypes of first-degree relatives.

Which statement about agonist and antagonist drugs is true? A. Both drugs types must interact with receptors to produce their intended responses. B. The primary target tissues for these types of drugs are invading bacteria and viruses. C. Antagonists drugs produce only intended responses, and agonist drugs produce both intended responses and side effects. D. These types of drugs are less likely to cause allergic responses than drugs that are neither agonists nor antagonists.

A. Both drugs types must interact with receptors to produce their intended responses.

What type of genetic test provides information about an asymptomatic person's risk for having a child with a specific autosomal-recessive disorder in the future? A. Carrier test B. Diagnostic test C. Newborn screening D. Predictive test

A. Carrier test

Which genetic-based disorders can be initially identified by the most common types of newborn blood screening? Select all that apply. A. Congenital hypothyroidism B. Cystic fibrosis C. Galactosemia D. Hereditary hemochromatosis E. Phenylketonuria F. Sickle cell disease

A. Congenital hypothyroidism C. Galactosemia E. Phenylketonuria F. Sickle cell disease

Which theory of carcinogenesis has the most support? A. DNA damage, which permits overexpression of oncogenes B. RNA damage, which results in incomplete protein formation C. Autoantibodies, which attack specific "self" tissues and organs D. The failure of embryonic tissues to undergo normal differentiation

A. DNA damage, which permits overexpression of oncogenes

Under which condition can preimplantation genetic testing be performed? A. During in vitro fertilization B. Between 4 to 6 weeks' gestation C. When paternity is unknown D. When an ultrasound indicates the fetus has a structural abnormality

A. During in vitro fertilization

A scientist is working to develop a genetic test that will screen embryos so that only those producing tall children with beautiful features will be implanted. What area of genetic work or studies does this example represent? A. Eugenics B. Cybernetics C. Cytogenetics D. Genetic imprinting

A. Eugenics

How many different genotypes are possible in any single mature spermatocyte of a man who is heterozygous at a single gene locus for a specific trait? A. One B. Two C. Four D. Eight

A. One

How is sickle cell trait different from sickle cell disease? A. People with sickle cell disease are homologous for the mutation, whereas those with sickle cell trait are heterozygous for the mutation. B. People with sickle cell trait are homologous for the mutation, whereas those with sickle cell disease are heterozygous for the mutation. C. Sickle cell disease results from an inherited mutation, and sickle cell trait results from an acquired mutation. D. Sickle cell trait results from an inherited mutation, and sickle cell disease results from an acquired mutation.

A. People with sickle cell disease are homologous for the mutation, whereas those with sickle cell trait are heterozygous for the mutation.

What is the function of the FMR1 gene? A. Promoting brain development and maintaining neuronal synapses B. Ensuring the expression of all other genes present on the X chromosome C. Preventing amyloid plaque deposits and formation of neuronal tangles in the brain D. Maintaining the structural integrity of the histone proteins surrounding the X chromosome

A. Promoting brain development and maintaining neuronal synapses

Why is Down syndrome the most common trisomy disorder seen among liveborn infants? A. The extra alleles from trisomies of larger chromosomes are embryo lethal. B. Nondisjunction occurs more frequently for chromosome 21 than for any other chromosome. C. Trisomies resulting from nondisjunction express fewer alleles than trisomies that result from unbalanced translocations. D. The incidence may not be truly higher but is recognized more often because the features of a baby with trisomy 21 are more obvious and not missed as often as are the more subtle features of other trisomies.

A. The extra alleles from trisomies of larger chromosomes are embryo lethal.

Which condition or statement exemplifies the concept of genomics rather than genetics? A. The gene for insulin is located on chromosome 11 in all people B. Expression of any single gene is dependent on inheriting two alleles C. Sex-linked recessive disorders affect males more often than females D. One allele for each gene is inherited from the mother, and one is inherited from the father

A. The gene for insulin is located on chromosome 11 in all people

How does the proteome differ from the genome? A. The proteome changes in response to intracellular and extracellular signals B. The genome changes in response to intracellular and extracellular signals C. The proteome is stable in somatic cells and unstable in germ cells, whereas the genome is stable in both somatic and germ cells D. The genome is stable in somatic cells and unstable in germ cells, whereas the proteome is stable in both somatics cells and germ cells

A. The proteome changes in response to intracellular and extracellular signals

Which statement reflects the criterion for autosomal-dominant transmission of single-gene traits? A. The risk for a person who is homozygous for the trait to transmit the trait to his or her children is 100% with each pregnancy B. The trait often remains unexpressed within a kindred for many generations until a change in environment promotes its expression C. Males in a kindred are more likely to express the trait when the mother has the trait, and females in a kindred are more likely to express the trait when the father has the trait D. Females in a kindred are more likely to express the trait when the mother has the trait, and males in a kindred are more likely to express the trait when the father has the trait

A. The risk for a person who is homozygous for the trait to transmit the trait to his or her children is 100% with each pregnancy

What is the primary purpose of a pedigree? A. To identify family members' places within a kindred and describe their medical history. B. To establish which person within a kindred is responsible for introducing a genetic mutation into the family. C. To determine the specific risk of any one family member to develop or pass on a genetic-based health problem. D. To establish which person within a kindred is responsible for bringing the family to the attention of a genetics professional.

A. To identify family members' places within a kindred and describe their medical history.

Which statement best describes the role of tumor suppressor genes in cancer development? A. Tumor suppressor genes control or modify the activity of oncogenes, reducing the risk for cancer development. B. The presence of tumor suppressor genes increases the risk for gene damage by environmental carcinogens. C. Tumor suppressor genes reduce/suppress immune function, increasing the risk for cancer development. D. Tumor suppressor genes are a type of oncogene that is only active in germline cells and tissues.

A. Tumor suppressor genes control or modify the activity of oncogenes, reducing the risk for cancer development.

Mating of a yellow male parakeet with a blue female parakeet resulted in 18 offspring. Four (two males; two females) had blue feathers, and 14 (eight females and six males) had yellow feathers. What allelic combinations and mode of inheritance can you determine from the evidence of the feather colors expressed? A. Yellow allele: dominant; blue allele: recessive; autosomal B. yellow allele: recessive; blue allele: dominant; autosomal C. yellow allele: dominant; blue allele: recessive; sex-linked D. yellow allele: recessive; blue allele: dominant; sex-linked

A. Yellow allele: dominant; blue allele: recessive; autosomal

Mutations in which of the following genes are now known to greatly increase the risk for developing breast cancer? Select all that apply. A. APC B. CDH1 C. CHEK2 D. DCC E. PALB2 F. PTEN

B. CDH1 C. CHEK2 E. PALB2 F. PTEN

A patient states that she has heard that the origin of most cancers is "genetic." What is the best response? A. "The development of most cancers is predetermined and not affected by environmental factors." B. "Cancers arise in cells that have alterations in the genes." C. "Cancer is more common among males than females." D. "The majority of cancers are inherited."

B. "Cancers arise in cells that have alterations in the genes."

A patient whose mother has Huntington disease is considering genetic testing but is not sure whether she really wants to know if she has the mutation. She asks you what you would do if your mother had the disease. What is your best response? A. "I would have the test so that I could decide whether to have children or to use adoption." B. "I can only tell you the benefits and the risks of testing; you must make this decision yourself." C. "Because there is no cure for this disease and testing would not be beneficial, I would not have the test." D. "You need to check with your brothers and sisters to determine whether testing for this disease would be appropriate for you."

B. "I can only tell you the benefits and the risks of testing; you must make this decision yourself."

Which feature or factor is the best predictor for delay of complications in a person who has sickle cell disease (SCD)? A. Male gender B. 20% or greater of HbF C. Having survived malaria D. Living in a geographic area that has cold winters

B. 20% or greater of HbF

What percentage of common cancers appears to be hereditary? A. 1% to 3% B. 5% to 15% C. 20% to 25% D. About 35%

B. 5% to 15%

What is the risk for a man with a 47,XYY karyotype to produce a child with a 47,XYY karyotype? A. 100% B. 50% C. 25% D. 0%

B. 50%

Which anomaly constitutes clinodactyly? A. An extra toe on one foot B. A laterally curved fifth finger C. Complete absence of fingers and toes D. Fusion of two fingers on the right hand

B. A laterally curved fifth finger

How is a congenital anomaly that requires intervention or management categorized? A. A dysmorphology B. A major anomaly C. A minor anomaly D. A disruption

B. A major anomaly

What is the risk for disease expression among the offspring of a woman who has an autosomal-recessive disorder when her partner is a carrier for the same disorder? A. All sons will be unaffected; all daughters will be carriers. B. All children have a 50% risk for being affected and a 50% risk for being a carrier. C. Daughters have a 50% risk for being affected; all sons will either be affected or carriers. D. Each child of either gender has a 50% risk of being a carrier, a 25% risk of having the disease, and a 25% risk of neither being a carrier nor having the disease.

B. All children have a 50% risk for being affected and a 50% risk for being a carrier.

Which type of genetic transmission promotes the continues existence of genetic mutations in single genes? A. Autosomal dominant B. Autosomal recessive C. Codominant D. Sex-linked

B. Autosomal recessive

With which type of inheritance pattern does the trait or disorder usually first appear among siblings rather than in parents of affected children? A. Autosomal dominant B. Autosomal recessive C. X-linked recessive D. Codominant

B. Autosomal recessive

How does an MSH2 gene mutation contribute to the development of colon cancer? A. Suppressor gene function is enhanced. B. DNA mutations are incorrectly repaired. C. Trinucleotide repeat sequences are enhanced. D. Drug resistance genes undergo amplification.

B. DNA mutations are incorrectly repaired.

Which action reflects promotion of genomic care as part of comprehensive health care? A. Calculating the odds ratios and recurrence risks of common complex health problems for all people B. Ensuring that genomic issues potentially influencing a person's health are incorporated into routine care C. Encouraging all people to undergo genetic testing as part of a proactive health screening and prevention program D. Instructing patients who undergo genetic testing about their obligation to inform family members regarding test results

B. Ensuring that genomic issues potentially influencing a person's health are incorporated into routine care

A woman's family history for breast cancer includes two paternal aunts who developed breast cancer before age 45. Which genetics professional would be most appropriate for assistance in helping this patient understand the health risk posed by this family history? A. Medical geneticist B. Genetic counselor C. Clinical geneticist D. Clinical laboratory geneticist

B. Genetic counselor

Which type of testing is most commonly used to diagnose sickle cell disease? A. Hematocrit and hemoglobin levels B. Hemoglobin electrophoresis C. Genetic mutation analysis D. Sweat chloride analysis

B. Hemoglobin electrophoresis

What is the result of a mutation occurring in a suppressor gene? A. Gain of a new function B. Loss of an existing function C. Increased "error-prone" DNA repair D. Increased unequal "crossing over" during meiosis I

B. Loss of an existing function

What is the most likely mechanism for a 45,X karyotype? A. Anticipation B. Nondisjunction C. Expansion D. Heteroplasmy

B. Nondisjunction

Genetic testing that examines an asymptomatic person's DNA sequence, looking for mutations that increase a person's susceptibility to a disease, is an example of which type of testing? A. Diagnostic testing B. Predispositional testing C. Presymptomatic testing D. Cytogenetic testing

B. Predispositional testing

A 12-year-old boy with Marfan syndrome complains to his nurse-practitioner, "My mother won't let me play football or do anything else. Isn't there something I can do besides sitting and playing video games?" Which of the following activities may be considered less risky for this child to perform? Select all that apply. A. Soccer (not the goalie position) B. Riding his bike with his friends C. Playing table tennis D. Competitive swimming E. Archery F. Recreational ice-skating G. Hiking low- to moderate-difficulty trails H. Basketball

B. Riding his bike with his friends C. Playing table tennis E. Archery F. Recreational ice-skating G. Hiking low- to moderate-difficulty trails

By which process does "promotion" assist in cancer development? A. Inflicting mutations at specific sites on the exposed cell's DNA B. Stimulating or enhancing cell division of cells damaged by a carcinogen C. Increasing the transformed cell's capacity for error-free DNA repair D. Making cancer cells appear more normal and escaping immunosurveillanc

B. Stimulating or enhancing cell division of cells damaged by a carcinogen

Preimplantation genetic diagnosis provides parents with which options? A. The ability to screen normally fertilized embryos for genetic traits after the first trimester B. The ability to select embryos for implantation that test negative for a familial disease mutation C. The opportunity to determine how many children they will conceive D. The ability to guarantee that they will have a healthy baby

B. The ability to select embryos for implantation that test negative for a familial disease mutation

Why should a tall teenager with Marfan syndrome avoid joining the high school basketball team? A. The excessively long limbs have reduced bone density, increasing the risk for fractures. B. The disorder is associated with weakened blood vessel walls that could rupture during strenuous activity. C. The disorder is associated with glycogen storage deficiency, and the individual could become seriously hypoglycemic during strenuous activity. D. Although people with Marfan syndrome are tall, they also have poor balance that impairs gross motor coordination, increasing the risk for injury.

B. The disorder is associated with weakened blood vessel walls that could rupture during strenuous activity.

What does a double horizontal line between a circle symbol and a square symbol as the only line directly connecting two individuals signify on a pedigree? A. The individuals are parent and child. B. The individuals are related by blood. C. The individuals are brother and sister. D. The individuals have mated without being married.

B. The individuals are related by blood.

What is the significance of a horizontal dashed line drawn between a male and a female? A. The two siblings are both adopted. B. The individuals have a casual sexual relationship and are not married. C. The individuals have a third-degree (or later) blood relationship with each other. D. Neither of the two individuals is a first- or second-degree relative of the proband.

B. The individuals have a casual sexual relationship and are not married.

What is the most likely explanation for a baby boy to have Tay-Sachs disease when the child's mother is not a carrier for the problem, but the father is a carrier? A. The mother is not really the biological parent of this child. B. The mother's normal gene allele is not expressed, and the father's Tay-Sachs allele is expressed. C. A new mutation occurred in the father's sperm in which the Tay-Sachs gene has become dominant. D. The father's Tay-Sachs gene has been translocated from its usual locus to the Y chromosome and thus is expressed in any male child.

B. The mother's normal gene allele is not expressed, and the father's Tay-Sachs allele is expressed.

Which personal factors indicate the possibility of a person having a BRCA1 or BRCA2 mutation? Select all that apply. A. The person has an adopted sister with ovarian cancer. B. The person's brother was diagnosed with breast cancer. C. The person has always been 20 lb overweight as an adult. D. The patient's father died of pancreatic cancer at age 44. E. The person is of Ashkenazi Jewish ethnicity. F. The person's 78-year-old grandmother was just diagnosed with breast cancer.

B. The person's brother was diagnosed with breast cancer. D. The patient's father died of pancreatic cancer at age 44. E. The person is of Ashkenazi Jewish ethnicity.

What is the best meaning for the term gene expression? A. The location of the specific gene allele on a specific autosomal chromosome B. The specific trait or protein coded for by a single gene is actually present C. The ability trait or protein coded for more than one trait or characteristic D. The loss of a trait or characteristic from one family generation to the next generation

B. The specific trait or protein coded for by a single gene is actually present

Which of the following mechanisms in fragile X syndrome (FXS) leads to expression of the disorder? A. Trinucleotide repeat sequences interspersed with the exons of the FMR1 gene, resulting in the production of an abnormal protein B. Trinucleotide repeat sequences causing methylation of the FMR1 gene, thus silencing its expression C. Increased production of microRNA molecules that interfere with the transcription of the FMR1 gene D. Increased production of microRNA molecules that interfere with the translation of the FMR1 gene

B. Trinucleotide repeat sequences causing methylation of the FMR1 gene, thus silencing its expression

Under which condition(s) would genetic testing for predisposition to an inherited disorder in a minor child be considered reasonable? A. When the family pedigree indicates an autosomal-dominant pattern of inheritance B. When the risk is high and prophylaxis to reduce the severity of the disorder is available C. When penetrance is high and the expected onset is middle adulthood D. When the mutation within a family is known and is specific

B. When the risk is high and prophylaxis to reduce the severity of the disorder is available

You are caring for a college professor who has been offered testing for her family's mutation in BRCA1. She expresses fear of genetic discrimination as a reason for refusing genetic testing. What do you tell her? A. "There is no need to be concerned about genetic discrimination." B. "I appreciate your concern, but there is no way your insurance company or employer will ever be able to get your genetic testing results." C. "There is now federal legislation banning genetic discrimination, and in addition, we will do everything we can to keep your results confidential." D. "There have been no instances of documented genetic discrimination in insurance or employment. This concern is overblown."

C. "There is now federal legislation banning genetic discrimination, and in addition, we will do everything we can to keep your results confidential."

What is the risk for a person to inherit an autosomal-dominant genetic disease-causing allele from a parent who is heterozygous if the disorder has a penetrance factor of 75%? A. 100% B. 75% C. 50% D. 25%

C. 50%

What is the expected outcome of any pregnancy or child produced by two parents who are each heterozygous for the Huntington disease allele? A. The couple cannot produce children who are unaffected. B. Homozygous offspring will express the disease in childhood instead of as an adult. C. A child who is homozygous for the mutated alleles is not likely to transmit the disorder to his or her children. D. Because of the possibility of incomplete or low penetrance, an unaffected offspring could have an affected child.

C. A child who is homozygous for the mutated alleles is not likely to transmit the disorder to his or her children.

Which ethnic group has the highest incidence of sickle cell disease (SCD)? A. Ashkenazi Jews B. Asian Americans C. African Americans D. French Canadians from Quebec

C. African Americans

In which situation are phenotype and genotype always the same? A. X-linked recessive traits B. X-linked dominant traits C. Autosomal-recessive traits D. Autosomal-dominant traits

C. Autosomal-recessive traits

Why are people of Ashkenazi Jewish descent more likely to be carriers of the mutations that cause Tay-Sachs and Gaucher disease? A. The environment of Eastern Europe increased their risk of developing a mutation. B. The common diet shared by these people has reduced their genetic diversity. C. Bottleneck effects have reduced the genetic diversity in this population. D. Being heterozygous for these diseases allowed them to survive cholera.

C. Bottleneck effects have reduced the genetic diversity in this population.

Which statement about a "germline" mutation in either a cancer suppressor gene or an oncogene is accurate? A. Cancer risk is increased only in sex hormone-sensitive tissues. B. The gene now has expressive potential but not penetrant potential. C. Cancer risk increases, but additional mutations are required for cancer development. D. A person inheriting such a mutation has a 100% risk for developing a specific cancer type.

C. Cancer risk increases, but additional mutations are required for cancer development.

Which clinical manifestation in a 6-month-old infant is most diagnostic for Tay-Sachs disease? A. Anemia and bruising B. Enlarged liver and spleen C. Cherry red spot on the retina D. Progressive cognitive impairment

C. Cherry red spot on the retina

Jessica (aged 32) is BRCA1 positive, which is known to greatly increase the risk for breast and ovarian cancer. She was tested because her mother, who had ovarian cancer, was BRCA1 positive. Jessica has decided to have both of her ovaries removed because she believes that, in her family, being BRCA1 positive increases the risk for ovarian cancer only. How should a genetic counselor respond to Jessica's statement? A. Encourage her to consider a bilateral mastectomy. B. Accept Jessica's explanation as a manifestation of her autonomy and remain nondirective in the interactions with her. C. Clarify that a BRCA1 mutation does not preferentially express ovarian cancer over breast cancer in any given family. D. Discuss Jessica's responsibility to inform all the other female members of her family about her BRCA1 status and cancer risk.

C. Clarify that a BRCA1 mutation does not preferentially express ovarian cancer over breast cancer in any given family.

Which processes of drug response are most subject to genetic variation? A. Drug dissolution in body fluids and drug binding to plasma proteins B. Rates of drug movement into and through the gastrointestinal tract C. Drug activation or deactivation and duration of drug actions D. Drug binding with receptors and drug blocking of receptors

C. Drug activation or deactivation and duration of drug actions

At what specific location on an X chromosome is a break most likely to occur in fragile X syndrome? A. The centromere B. End of the p arm C. End of the q arm D. Within the nucleosome

C. End of the q arm

A person who is worried that he may have inherited the gene mutation for Huntington disease is told that he has the "wild-type" form of this gene. What is the best interpretation of this finding? A. His gene for Huntington disease (HD) has more "hot spots" for mutations than the general population B. His Huntington disease has unusual mutations of unknown significance C. His Huntington disease gene is considered normal D. He has no Huntington disease gene

C. His Huntington disease gene is considered normal

Under what normal condition are genotype and phenotype always the same? A. Euploidy of alleles B. Aneuploidy of alleles C. Homozygosity of alleles D. Heterozygosity of alleles

C. Homozygosity of alleles

Which feature is associated exclusively with sporadic cancer? A. The cause is unknown. B. It usually affects both bilateral organs. C. It occurs at the same frequency within a kindred as in the general population. D. It is more likely to occur in younger people with few environmental risks than in older people.

C. It occurs at the same frequency within a kindred as in the general population.

A male patient is tall and has some gynecomastia along with a low sperm count. During infertility testing, he was found to have a 47,XXY karyotype. Which disorder is consistent with these findings? A. Normal male B. Turner syndrome C. Klinefelter syndrome D. Testicular feminization syndrome

C. Klinefelter syndrome

Which tissue is most likely to provide an adequate DNA sample for genetic testing? A. Distal ends of hair shafts B. Mature red blood cells C. Nasal epithelial cells D. A mummy's tooth

C. Nasal epithelial cells

Which trait or disorder has both an autosomal-dominant form and an autosomal-recessive form? A. Widow's peak B. Diabetes mellitus type 2 C. Polycystic kidney disease D. Taste sensitivity to phenylthiocarbamate (PTC)

C. Polycystic kidney disease

Genetic testing of an asymptomatic woman whose sister is positive for the mutation that is responsible for an autosomal-dominant disorder that has a 70% penetrance rate would fall into which testing category? A. Diagnostic predisposition B. Diagnostic presymptomatic C. Predictive predisposition D. Predictive presymptomatic

C. Predictive predisposition

How do genetics counselors provide genetic/genomic information to patients and families in a nondirective manner? A. Providing only the information the patient or family specifically requests B. Skillfully directing the patient and family toward the best choice that is supported by appropriate research C. Presenting all facts and available options in a manner that neither promotes nor excludes any legally permitted decision or action D. Filtering management options and focusing on the information that will support the decision they believe is right for the individual patient/family

C. Presenting all facts and available options in a manner that neither promotes nor excludes any legally permitted decision or action

How does the drug Endari reduce the manifestations of sickle cell disease? A. Promoting faster red blood cell production B. Increasing the concentration of fetal hemoglobin (HbF) C. Reducing oxidate stress and increasing the life span of red blood cells D. Correcting the mutation of one allele so that the person has sickle cell trait instead of sickle cell disease

C. Reducing oxidate stress and increasing the life span of red blood cells

How does apoptosis contribute to healthy organ and whole-body function? A. Maintains telomeric DNA B. Allows cells to differentiate rather than to undergo mitosis C. Removes old or damaged cells from an organ population D. Activates oncogenes when cells are damaged or necrotic

C. Removes old or damaged cells from an organ population

A woman whose sister tested positive for a specific mutation in the BRCA1 gene, which increases the risk for breast and ovarian cancer, is found not to have that mutation but does have a mutation of unknown significance near the known mutation site. How should this woman be counseled? A. She should be informed that her risk for breast cancer is greater than that of the general population but not as great as her sister's risk. B. She should be informed that because she does not have the mutation, her risk for breast cancer is not greater than that of the general population. C. She should be informed that she does not have the specific mutation but that because another mutation is present, she should be vigilant about screening. D. She should be informed of her gene-mutation status and be presented with all the available prophylaxis options and reconstruction options.

C. She should be informed that she does not have the specific mutation but that because another mutation is present, she should be vigilant about screening.

Which pair of relatives represents a first-degree relationship? A. Grandfather and grandson B. Aunt and nephew C. Sister and brother D. Two cousins

C. Sister and brother

Which feature is common among people who have Klinefelter syndrome (47,XXY) or a karyotype with 47,XXX but not among people who have Down syndrome or Edward syndrome? A. Severely reduced cognition B. Cleft palate C. Tall stature D. Infertility

C. Tall stature

Which statement regarding inheritance of an autosomal-dominant gene allele with known variability in expressivity is true? A. A person with low expressivity of the trait has a higher probability of having a child who does not express the trait at all B. A person with high expressivity of the trait has a greater risk of having a child who expresses the trait to an even greater degree C. The degree of expressivity of a given autosomal-dominant trait with known variability cannot be predicted by analyzing parental expression D. The degree of expressivity of a given autosomal-dominant trait with known variability is greater when the transmitting parent is the same sex as the child

C. The degree of expressivity of a given autosomal-dominant trait with known variability cannot be predicted by analyzing parental expression

How are twins indicated on a pedigree? A. The two gender symbols are placed on top of each other. B. Each of the gender symbols is surrounded by an inward-facing set of brackets. C. The vertical lines to each twin begin at the same point on the parents' horizontal mating line. D. The one born first has a vertical line connected to the parents' horizontal mating line; the twin born second has a vertical line extending down from the first twin's gender symbol.

C. The vertical lines to each twin begin at the same point on the parents' horizontal mating line.

Why are people who have poor DNA repair mechanisms at greater risk for cancer development? A. Their cancers are usually resistant to chemotherapy. B. They have sustained the initial "hit" in all cells and tissues. C. Their somatic mutations are more likely to be permanent. D. They have greater exposure to environmental carcinogens.

C. Their somatic mutations are more likely to be permanent.

On a five-generation pedigree, which feature distinguishes an X-linked-dominant disorder in which males and females are equally affected from an autosomal-recessive pattern of inheritance? A. The disorder is not apparent until adulthood B. Unaffected individuals do not have affected children C. There are no instances of an affected father transmitting the disorder to his son D. Unaffected parents (who do not express the disorder) do have affected children

C. There are no instances of an affected father transmitting the disorder to his son

Which description is the best example of "genomic imprinting"? A. A child inherits a trait that his paternal grandfather expressed but that his father did not express B. Boys can inherit only masculine traits from their fathers because women do not have a Y chromosome C. There is a qualitative difference in some gene alleles based on whether they are inherited from the mother or the father D. When the number of sex chromosomes is greater than normal, the resulting individual is most often infertile

C. There is a qualitative difference in some gene alleles based on whether they are inherited from the mother or the father

When constructing a pedigree around a specific health problem, what is the minimal number of generations needed to accurately assess the presence or absence of a genetic factor in disease development? A. One B. Two C. Three D. Four

C. Three

A patient asks you whether the Genetic Information and Nondiscrimination Act (GINA) means that his insurance company is required to pay for his genetic testing if he elects to have it done. What is your best response? A. "Yes, if you agree to share the test results with your family, your health-care provider, and your insurance company." B. "Yes, if other family members have already been found positive for a disease-causing mutation." C. "No, unless testing finds a specific disorder for which a current medical intervention has been proven effective." D. "No, it only protects against discrimination and does not require insurance companies to pay for testing."

D. "No, it only protects against discrimination and does not require insurance companies to pay for testing."

What is the risk for a man who has Down syndrome to produce a child with Down syndrome with a woman who has a normal karyotype? A. 100% B. 50% C. 5% D. 0%

D. 0%

When geneticists assess dysmorphology, what do they consider? A. The "gestalt" B. The general feel and overall appearance of the patient C. Specific dysmorphic features, such as the shape of the face and the position of the ears D. All of the above

D. All of the above

Which cancer type is associated with a 9;22 translocation t(9;22)? A. Acute promyelocytic leukemia B. Acute lymphocytic leukemia C. Chronic lymphocytic leukemia D. Chronic myelogenous leukemia

D. Chronic myelogenous leukemia

What is the significance of a pedigree symbol consisting of a square with a diagonal slash mark through it? A. Affected female B. Affected male C. Deceased female D. Deceased male

D. Deceased male

What health advantage does sickle cell trait or disease confer on the person who has it? A. Decreased risk for type 1 diabetes mellitus B. Decreased risk for hypercholesterolemia C. Decreased risk for fulminating cholera D. Decreased risk for malaria

D. Decreased risk for malaria

Which substance fails to form normally in individuals with Marfan syndrome? A. Elastin B. Glycogen C. Collagen D. Fibrillin

D. Fibrillin

Which single physical feature is most often associated with a 47,XXX karyotype? A. Infertility B. Large breasts C. Female-pattern baldness D. Height greater than siblings

D. Height greater than siblings

Which condition or health problem is more common in women who have an FMR1 mutation? A. Emotional instability with inappropriate expression of anger B. Patchy areas of decreased skin pigmentation C. Progressive skeletal muscle weakness D. Menopause before age 40 years

D. Menopause before age 40 years

Which of the following is a goal of pharmacogenetics? A. Producing "blockbuster drugs" that will work equally well for everyone B. Bringing down the cost of pharmaceutical manufacturing C. Developing drugs that will treat very rare diseases D. Reducing adverse reactions

D. Reducing adverse reactions

Which specific type of genetic problem causes sickle cell disease? A. Deletion of an exon B. Deletion of an intron C. Unbalanced translocation D. Single-nucleotide polymorphism

D. Single-nucleotide polymorphism

Which manifestation is a characteristic feature of untreated phenylketonuria (PKU)? A. Increased skin pigmentation B. Excessive urination C. Fragile bones D. Small stature

D. Small stature

What is the function of a normal BRCA1 gene? A. Enhances overall cell growth during puberty B. Directs the development of normal breast tissue C. Increases the expression of cytochrome P450 enzymes D. Suppresses the growth potential of a variety of oncogenes

D. Suppresses the growth potential of a variety of oncogenes

Which person is an obligate carrier of an autosomal-recessive single-gene trait or disorder without expressing the trait or disorder A. The son of a man with classic hemophilia B. The daughter of a woman with Marfan syndrome C. The son of a man who expresses a widow's peak hairline D. The daughter of a woman who expresses attached earlobes

D. The daughter of a woman who expresses attached earlobes

What is the best explanation for a person whose karyotype from blood cells shows nearly all cells to have trisomy 21 to have 10 clinical manifestations of Down syndrome and an above-average intelligence? A. The trisomy was a result of nondisjunction of paternal gametes instead of maternal gametes. B. The person has pseudo-Down syndrome, in which environmental conditions caused the person to have development that mimics only the physical manifestations. C. The person has genomic imprinting, in which the paternal number 21 chromosome is not expressed, and both maternally derived number 21 chromosomes are expressed. D. The person has mosaicism of trisomy 21, with blood cells having a high proportion and neurons having a low proportion of cells, with three number 21 chromosomes

D. The person has mosaicism of trisomy 21, with blood cells having a high proportion and neurons having a low proportion of cells, with three number 21 chromosomes

Why is predictive testing for Huntington disease avoided for a 4-year-old child who has one grandparent with the disorder? A. Unless one of the parents is positive for the gene mutation, a negative finding would be noninformative. B. The Huntington disease mutation is poorly penetrant and may never be expressed even when inherited. C. A 4-year-old child cannot understand or participate in the genetic counseling process. D. There are no effective primary or secondary prevention strategies for this disorder.

D. There are no effective primary or secondary prevention strategies for this disorder.

What is the expected outcome of pregnancy for women with phenylketonuria (PKU) when the blood levels of phenylalanine are high throughout the pregnancy? A. Most births are post-mature. B. There is a high incidence of infertility. C. The infant develops PKU. D. There is a high incidence of cardiovascular birth defects.

D. There is a high incidence of cardiovascular birth defects.

How does an acquired mutation in a somatic cell gene leading to cancer development affect a person's ability to pass on a predisposition for that cancer type to his or her children? A. The predisposition can only be passed on if the person with the somatic cell mutation is female. B. The risk for predisposition is dependent upon which tissue type experienced the somatic mutation. C. Multiple somatic mutations are required for passing on a predisposition to cancer development. D. There is no risk of passing on a cancer predisposition from a somatic cell mutation.

D. There is no risk of passing on a cancer predisposition from a somatic cell mutation.