GENE 301 Chpt 6 quiz

Problem 2: Using the information from below, what is the probability that a random person has blood that is both type O blood and type M?(Ignore the Rhesus locus.) The Rhesus or Rh factor in blood typing also has multiple alleles, but the alleles can be classified into two types, positive and negative. Rh+ is dominant over Rh−. The allele frequencies of these alleles are indicated below. The MN blood antigen trait is controlled by two codominant alleles at a single locus. Type M individuals are homozygous for the M allele, type MN individuals are heterozygous, and type N individuals are homozygous for the N allele (codominant). In the United States, the allele frequencies for this blood group are also indicated below. ABO Rhesus MN [iO] = 0.50 [Rh+] = 0.6 [M] = 0.5 [IA] = 0.35 [Rh-] = 0.4 [N] = 0.5 [IB] = 0.15 A. 0.0625 B. 0.122 C. 0.1378 D. 0.0756 E. 0.152

A

Problem 3: Using the information from below, what will be the frequency of a person in the U.S. population with type B, N, and Rh+ blood (calculate one locus at a time)? The Rhesus or Rh factor in blood typing also has multiple alleles, but the alleles can be classified into two types, positive and negative. Rh+ is dominant over Rh−. The allele frequencies of these alleles are indicated below. The MN blood antigen trait is controlled by two codominant alleles at a single locus. Type M individuals are homozygous for the M allele, type MN individuals are heterozygous, and type N individuals are homozygous for the N allele (codominant). In the United States, the allele frequencies for this blood group are also indicated below. ABO Rhesus MN [iO] = 0.50 [Rh+] = 0.6 [M] = 0.5 [IA] = 0.35 [Rh-] = 0.4 [N] = 0.5 [IB] = 0.15 A. 0.0362 B. 0.0371 C. 0.0252 D. 0.0680 E. 0.0791

A

Problem 5: In an Alaskan village of Inuit Indians, an inordinate number of cats have 6 toes on each foot. The trait of polydactyly (many digits) is caused by a DOMINANT allele. If 22% of the cats have 6 digits per foot, what is the ALLELE frequency of this dominant allele in this population of cats? A. 0.117 B. 0.22 C. 0.883 D. 0.183 E. 0.207

A

Problem 1: The ABO blood group in humans is controlled by a single locus with three different alleles. Homozygosity for IA produces type A blood. Homozygosity for IB produces type B blood. Homozygosity for iO produces type O blood. Type AB blood is produced by the genotype IA/IB. iO is recessive to IA and IB, thus IA/ iO gives type A blood and IB/ iO gives type B blood. In the United States, the ALLELE frequencies for the ABO alleles are given below. The Rhesus or Rh factor in blood typing also has multiple alleles, but the alleles can be classified into two types, positive and negative. Rh+ is dominant over Rh−. The allele frequencies of these alleles are indicated below. The MN blood antigen trait is controlled by two codominant alleles at a single locus. Type M individuals are homozygous for the M allele, type MN individuals are heterozygous, and type N individuals are homozygous for the N allele (codominant). In the United States, the allele frequencies for this blood group are also indicated below. ABO Rhesus MN [iO] = 0.50 [Rh+] = 0.6 [M] = 0.5 [IA] = 0.35 [Rh-] = 0.4 [N] = 0.5 [IB] = 0.15 What is the probability that a random person in the United States has type B blood? (Ignore the Rhesus and MN loci.) A. 0.01 B. 0.1725 B. 0.13 D. 0.12 E. 0.0225

B

Problem 4: Albinism occurs in the United States at a frequency of one in every 16,000 live births. Assume that this trait is autosomal and recessive (c/c). At what frequency are heterozygous for albinism expected in this population? A. 0.0168 B. 0.0157 C. 0.99 D. 0.0181 E. 0.0198

B

Problem 7: In snapdragons, the allele that produces red pigment is INCOMPLETELY DOMINANT. RR results in red flowers, Rr in pink, and rr produces white flowers. In a field of snapdragons, there are 320 red flowering plants, 430 pink flowering plants, and 250 white flowering plants. What is the BEST estimate for the allele frequency of the "r" allele (total = 1,000)? A. 0.566 B. 0.465 C. 0.535 D. 0.205 E. 0.50

B

Problem 8: A rare phenotype encountered among the mountain people of West Virginia involves the absence of a cytochrome cofactor. The trait is recessive and when homozygous gives affected individuals, a distinctly blue color to their skin and chronic weakness. The defect can be cured completely by supplying the cofactor by pills (about one pill each day keeps them looking and feeling normal). Such "blue" people occur at a frequency of about one in 8,100 births in West Virginia populations. What is the allele frequency of this gene? A. 0.000123 B. 0.0111 C. 0.0219 D. 0.00024 E. None of these

B

Problem 10: (Challenge) From the pedigree, if individual B marries someone from the population at large (where the trait is expressed one in 8,100 people), what is the probability they have a child expressing the trait? A. 0.0111 B. 0.000123 C. 0.0037 D. 0.00004 E. 0.0074

C

Problem 6: Hemophilia is a sex-linked disease (on the X chromosome) that is a defect in the clotting mechanism of the blood. It is extremely rare in females, but among males it occurs at a frequency of about 1 birth in 700 male births in the United States. What is the allele frequency of this trait? A. 0.05 B. 0.0025 C. 0.00411 D. 0.00143 E. 0.0378

D

Problem 9: Consider the pedigree to the right of the "blue" people trait. Shaded individuals are affected by the trait. Remember to use the inbreeding convention as it applies. Five generation pedigree. Individual I-2 is married twice. In her marriage to individual I-1, she had a son (II-2). In her marriage to individual I-3, she had a daughter (II-3). Individual II-2 married a woman from outside the family (II-1) and had a daughter (III-2). Individual II-3 married a man from outside the family (II-4) and had a son (III-3). Individual III-2 married a man from outside the family (III-1) and had a son (IV-1). Individual III-3 married a woman from outside the family (III-4) and had a daughter (IV-2). Individuals IV-1 and IV-2 marry and have two daughters (V-1 and V-2). V-1 is labeled A and is expressing the blue trait. V-2 is labeled B and is not expressing the blue trait. What is the inbreeding coefficient for individual B? A. 1/16 B. 1/32 C. 1/64 D. 1/128 E. 1/256

D