Genetics chapter 9
What is a restriction enzyme? What structure does it recognize? What type of chemical bond does it cleave? Be as specific as possible.
. A restriction enzyme recognizes and binds to a specific DNA sequence and then cleaves a (covalent) phosphoester bond in each of two DNA strands.
Explain and draw the structural feature of a dideoxyribonucleotide that causes chain termination.
A dideoxynucleotide is missing the -OH group at the 3' position. When the 5' end of a dideoxynucleotide is added to a growing strand of DNA, another phosphoester bond cannot be formed at the 3' position. Therefore, the dideoxynucleotide terminates any further addition of nucleotides to the growing strand of DNA.
What is the gene pool? How is a gene pool described in a quantitative way?
A gene pool is all of the genes present in a particular population. Each type of gene within a gene pool may exist in one or more alleles. The prevalence of an allele within the gene pool is described by its allele frequency. If a gene is monomorphic, the allele frequency is close to 100%. If it is polymorphic, each allele has a frequency that is between 1 and 99%. The sum of all the allele frequencies for a particular gene will add up to 100%.
In genetics, what does the term population mean? Pick any species you like and describe how its population might change over the course of many generations.
A population is a group of interbreeding individuals. Let's consider a squirrel population in a forested area. Over the course of many generations, several things could happen to this population. A forest fire, for example, could dramatically decrease the number of individuals and thereby cause a bottleneck. This would decrease the genetic diversity of the population. A new predator may enter the region and natural selection may select for the survival of squirrels that are best able to evade the predator. Another possibility is that a group of squirrels within the population may migrate to a new region and found a new squirrel population.
Why is a thermostable form of DNA polymerase (e.g., Taq polymerase) used in PCR?
A thermostable form of DNA polymerase (e.g., Taq polymerase) is used in PCR because each PCR cycle involves a heating step to denature the DNA. This heating step would inactivate most forms of DNA polymerase. However, Taq polymerase is thermostable and can remain functional after many cycles of heating and cooling.
17. In a large herd of 5468 sheep, 76 animals have yellow fat, compared with the rest of the members of the herd, which have white fat. Yellow fat is inherited as a recessive trait. This herd is assumed to be in Hardy-Weinberg equilibrium. a. What are the frequencies of the white and yellow fat alleles in this population? b. Approximately how many sheep with white fat are heterozygous carriers of the yellow allele?
A. Let W represent the white fat allele and w represent the yellow fat allele. Assuming HardyWeinberg equilibrium, we can let p 2 represent the genotype frequency of WW animals, and then Ww would be 2pq and ww would be q 2. The only genotype frequency we know is that of the ww animals. ww-q2 (76/5468) →q=0.12 p 1-0.12 0.88 B. The heterozygous carriers are represented by 2pq. If we use the values of p and q, which were calculated in part A: 2pq = 2(0.88)(012) = 0.21 Approximately 21% of the animals would be heterozygotes with white fat. If we multiply 0.21 times the total number of animals in the herd:
In a large herd of 5468 sheep, 76 animals have yellow fat, compared with the rest of the members of the herd, which have white fat. Yellow fat is inherited as a recessive trait. This herd is assumed to be in Hardy-Weinberg equilibrium. a. What are the frequencies of the white and yellow fat alleles in this population?
A. Let W represent the white fat allele and w represent the yellow fat allele. Assuming HardyWeinberg equilibrium, we can let p 2 represent the genotype frequency of WW animals, and then Ww would be 2pq and ww would be q 2. The only genotype frequency we know is that of the ww animals. ww-q2 (76/5468) →q=0.12 p=1-0.12=0.88
Cystic fibrosis (CF) is a recessive autosomal trait. In certain Caucasian populations, the number of people born with this disorder is about I in 2500. Assuming Hardy-Weinberg equilibrium for this trait: a. What are the frequencies for the normal and CF alleles? b. What are the genotype frequencies of homozygous normal, heterozygous, and homozygous affected individuals? c. Assuming random mating, what is the probability that two phenotypically unaffected heterozygous carriers will choose each other as mates?
A. The genotype frequency for the CF homozygote is 1/2,500, or 0.004. This equals q 2. The allele frequency is the square root of this value, which equals 0.02. The frequency of the corresponding normal allele equals 1- 0.02 = 0.98. b. The frequency for the CF homozygote is 0.004; for the unaffected homozygote, (098)2 = 0.96; and for the heterozygote, 2(0.98)(0.02), which equals 0.039. c.If a person is known to be a heterozygous carrier, the chances that this particular person will happen to choose another as a mate is equal to the frequency of heterozygous carriers in the population, which equals 0.039, or 3.9%. The chances that two randomly chosen individuals will choose each other as mates equals 0.039 x 0.039 = 0.0015, or 0.15%.
With regard to DNA microarrays, answer the following questions: c. How is hybridization detected?
After hybridization, the array is washed and placed in a laser scanner that scans each pixel (the smallest element in a visual image). After correction for local background, the final fluorescence intensity for each spot is obtained by averaging across the pixels in each spot. This results in a group of fluorescent spots at defined locations in the microarray.
Describe the important features of cloning vectors. Explain the purpose of selectable marker genes in cloning experiments.
All vectors have the ability to replicate when introduced into a living cell. This ability is due to a DNA sequence known as an origin of replication, which determines the host cell specificity of a vector. Modern vectors also contain convenient restriction sites where geneticists can insert fragments of DNA. These vectors also contain selectable markers, which are genes that confer some selectable advantage for the host cell that carries them. The most common selectable markers are antibiotic-resistance genes, which confer resistance to antibiotics that would normally inhibit the growth of the host cell.
State for each of the following whether it is an example of an allele, genotype, and/or phenotype frequency: Genotype frequency c. The number of new mutations for achondroplasia, a genetic disorder, is approximately 5 x 10-5.
Allele frequency
The term polymorphism can refer to both genes and traits. b. If a gene is polymorphic, does the trait that the gene affects also have to be polymorphic? Explain why or why not.
Alleles do not always cause differences in phenotype. A single- base substitution in a gene may not affect the amino acid sequence of the encoded polypeptide (e.g., the base change may affect the wobble base) or a singlebase change might alter the amino acid sequence, but not in a way that alters the protein's function. Therefore, gene polymorphism does not always result in phenotypic polymorphism.
Chapter Gene polymorphisms can be detected using a variety of cellular and molecular techniques. Which techniques would you use to detect gene polymorphisms at the following levels? b. RNA level
At the RNA level, a Northern blot may reveal genetic variation. If the RNA encoded by two different alleles has a different size, this can be detected in a Northern blot.
Gene polymorphisms can be detected using a variety of cellular and molecular techniques. Which techniques would you use to detect gene polymorphisms at the following levels? c. Polypeptide level
At the protein level, gel electrophoresis with a Western Blot may reveal genetic variation. Another approach is to study the function of an enzyme using a biochemical assay of its activity.
The ability to roll your tongue is inherited as a recessive trait. The frequency of the rolling allele is approximately 0.6, and the dominant (nonrolling) allele is 0.4. What is the frequency of individuals who can roll their tongues?
Because this is a recessive trait, only the homozygotes for the rolling allele will be able to roll their tongues. If p equals the rolling allele and q equals the nonrolling allele, the Hardy-Weinberg equation predicts that the frequency of homozygotes who can roll their tongues would be p 2. In this case, p 2 = (0.6)2 = 0.36, or 36%.
What is DNA fingerprinting? How can it be used in human identification?
DNA fingerprinting is a method of identification based on the properties of DNA. Minisatellites and microsatellite sequences are variable with regard to size in natural populations. This variation can be seen when DNA fragments are subjected to gel electrophoresis. Within a population, any two individuals (except for identical twins) will display a different pattern of DNA fragments, which is called their DNA fingerprint.
Do the following examples describe directional, disruptive, balancing, or stabilizing selection? d. Sturdy stems and leaves among plants exposed to windy climates
Directional. Sturdy stems and leaves will promote survival in windy climates.
Do the following examples describe directional, disruptive, balancing, or stabilizing selection? b. Thick fur among mammals exposed to cold climates
Directional. The thicker the fur, the more likely that survival will occur.
Do the following examples describe directional, disruptive, balancing, or stabilizing selection? a. Polymorphisms in snail color and banding pattern as described in Figure 25.12
Disruptive. There are multiple environments that favor different phenotypes.
Describe what happens to allele frequencies as a result of the bottleneck effect. Discuss the relevance of this effect with regard to species that are approaching extinction.
During the bottleneck effect, allele frequencies are dramatically altered due to genetic drift. In extreme cases, some alleles are lost, while others may become fixed at 100%. The overall effect is to decrease genetic diversity within the population. This may make it more difficult for the species to respond in a positive way to changes in the environment. Species that are approaching extinction also face a bottleneck as their numbers decrease. The loss of genetic diversity may make it even more difficult for the species to rebound.
Which of the following statements are true about molecular markers? c. We can follow the transmission of a molecular marker by analyzing the phenotype (i.e., the individual's bodily characteristics) of offspring.
False, the marker may not carry a gene that affects phenotype.
Which of the following statements are true about molecular markers? a. All molecular markers are segments of DNA that carry specific genes.
False, they do not have to carry genes
With regard to genetic drift, are the following statements true or false? If a statement is false, explain why. c. Genetic drift promotes genetic diversity in large populations.
False; it causes allele loss or fixation, which results in less diversity.
Outline the general strategy of metagenomics.
First, researchers obtain a sample from the environment. This could be soil sample, a water sample from the ocean, or a fecal sample from a person. After the sample is filtered, the cells within the sample are lysed and the DNA is extracted and purified. During this procedure, the purified DNA is sheared and contains fragments of different sizes. The DNA fragments are then randomly inserted into a cloning vector and transformed into a host cell. The result is a DNA library of thousands or tens of thousands of cells, each carrying a DNA fragment from the metagenome. All cells together constitute the metagenomic library. The members of the library are then subjected to shotgun DNA sequencing to identify the genes they may contain. Note: the cloning step may be skipped if certain types of DNA sequencing methods, such as pyrosequencing, are used.
Two populations of antelope are separated by a mountain range. The antelope are known to occasionally migrate from one population to the other. Migration can occur in either direction. Explain how migration affects the following phenomena: c. Genetic drift in the two populations
Genetic drift depends on population size. When two populations intermix, this has the effect of increasing the overall population size. In a sense, the two smaller populations behave somewhat like one big population. Therefore, the effects of genetic drift are lessened when the individuals in two populations can migrate. The net effect is that allele loss and allele fixation are less likely to occur due to genetic drift.
Why is genetic drift more significant in small populations? Why does it take longer for genetic drift to cause allele fixation in large populations than in small ones?
Genetic drift is due to sampling error, and the degree of sampling error depends on the population size. In small populations, the relative proportion of sampling error is much larger. If genetic drift is moving an allele toward fixation, it will take longer in a large population because the degree of sampling error is much smaller.
State for each of the following whether it is an example of an allele, genotype, and/or phenotype frequency: The percentage of carriers of the sickle cell allele in West Africa is approximately 13%.
Genotype frequency
Southern and Northern blotting depend on the phenomenon of hybridization. In these two techniques, explain why hybridization occurs. Which member of the hybrid is labeled
Hybridization occurs due to the hydrogen bonding of complementary sequences. Due to the chemical properties of DNA and RNA strands, they form double-stranded regions when the base sequences are complementary. In a Southern and Northern experiment, the cloned DNA is labeled and used as a probe.
A researcher is interested in a gene found on human chromosome 21. Describe the expected results of a FISH experiment using a probe that is complementary to this gene. How many spots would you see if the probe was used on a sample from an individual with 46 chromosomes versus an individual with Down syndrome?
If the sample was from an unaffected individual, two spots (one on each copy of chromosome 21) would be observed. Three spots would be observed if the sample was from a person with Down syndrome, because the person has three copies of chromosome 21.
Describe the similarities and differences among directional, balancing, disruptive, and stabilizing selection.
In all cases, these forms of natural selection favor one or more phenotypes because such phenotypes have a reproductive advantage. However, the patterns differ with regard to whether a single phenotype or multiple phenotypes are favored, and whether the phenotype that is favored is in the middle of the phenotypic range or at one or both extremes. Directional selection favors one phenotype at a phenotypic extreme. Over time, natural selection is expected to favor the fixation of alleles that cause these phenotypic characteristics. Disruptive selection favors two or more phenotypic categories. It will lead to a population with a balanced polymorphism for the trait. Examples of balancing selection are heterozygote advantage and negative-frequency dependent selection. These promote a stable polymorphism in a population. Stabilizing selection favors individuals with intermediate phenotypes. It tends to decrease genetic diversity because alleles that favor extreme phenotypes are eliminated.
What are two ways to produce many copies of a gene?
In conventional gene cloning, many copies are made because the vector replicates to a high copy number within the cell, and the cells divide to produce many more cells. In PCR, the replication of the DNA to produce many copies is facilitated by primers, deoxyribonucleoside triphosphates (DNTPS), and Taq polymerase.
In the term genetic drift, what is drifting? Why is this an appropriate term to describe this phenomenon?
In genetic drift, allele frequencies are drifting. Genetic drift is an appropriate term because the word drift implies a random process. Nevertheless, drift can be directional. A boat may drift from one side of a lake to another. It would not drift in a straight path, but the drifting process will alter its location. Similarly, allele frequencies can drift up and down and eventually lead to the elimination or fixation of particular alleles within a population.
With regard to DNA microarrays, answer the following questions: b. What is hybridized to the microarray?
In most cases, fluorescently labeled CDNA is hybridized to the microarray, though labeled genomic DNA or RNA could also be used.
Does inbreeding affect allele frequencies? Why or why not? How does it affect genotype frequencies? With regard to rare recessive diseases, what are the consequences of inbreeding in human populations?
In the absence of other factors, inbreeding does not alter allele frequencies, because it does not favor the transmission of one allele over another. It simply increases the likelihood of homozygosity (which is a genotype frequency). In human populations, inbreeding increases the frequency of individuals who are homozygous for rare recessive alleles that cause human disease
Starting with a sample of RNA that contains the mRNA for the B-globin gene, explain how you could create many copies of the B-globin cDNA using reverse transcriptase PCR.
Initially, the mRNA would be mixed with reverse transcriptase and nucleotides to create a complementary strand of DNA. Reverse transcriptase also needs a primer. This could be a primer that is known to be complementary to the B-globin mRNA. Alternatively, mature mRNAs have a polyA tail, so you could add a primer that consists of many Ts, called a poly-dT primer. After the complementary DNA strand has been made, the sample would then be mixed with primers, Taq polymerase, and nucleotides and subjected to the standard PCR protocol. Note: the PCR reaction would have two kinds of primers. One primer would be complementary to the 5' end of the mRNA and would be unique to the B-globin sequence. The other primer would be complementary to the 3 end. This second primer could be a poly-dT primer or it could be a unique primer that would bind slightly upstream from the polyA-tail region.
Some vectors used in cloning experiments contain bacterial promoters that are adjacent to unique cloning sites. This makes it possible to insert a gene sequence next to the bacterial promoter and express the gene in bacterial cells. These are called expression vectors. If you wanted to express a eukaryotic protein in bacterial cells, would you insert genomic DNA or cDNA into the expression vector? Explain your choice.
It would be necessary to use CDNA so that the gene would not carry any introns. Bacterial cells do not contain spliceosomes (which are described in Chapter 14). To express a eukaryotic protein in bacteria, a researcher would clone CDNA into bacteria, because the CDNA does not contain introns.
Here are traditional DNA fingerprints of five people: a child, mother, and three potential fathers: Which males can be ruled out as being the father? Explain your answer. If one of the males could be the father, explain the general strategy for calculating the likelihood that he could match the offspring's DNA fingerprint by chance alone. (See More Genetic TIPS # 4 before answering this question.)
Male 2 is the potential father, because he contains the bands that are found in the offspring but are not found in the mother. To calculate the probability, you would have to know the probability of having each of the types of bands that match. In this case, for example, male 2 and the offspring have four bands in common. As a simple calculation, you could eliminate the four bands that the offspring shares with the mother. If the probability of having each paternal band is 1/4, the chances that this person is not the father are (1/4)*.
Two populations of antelope are separated by a mountain range. The antelope are known to occasionally migrate from one population to the other. Migration can occur in either direction. Explain how migration affects the following phenomena: a. Genetic diversity in the two populations
Migration will increase the genetic diversity in both populations. A random mutation could occur in one population to create a new allele. This new allele could be introduced into the other population via migration.
For each of the following, decide if it could be appropriately described as a genome: b. Human chromosome 11
No, this is only one chromosome in the genome
State for each of the following whether it is an example of an allele, genotype, and/or phenotype frequency: a. Approximately 1 in 2500 Caucasians is born with cystic fibrosis.
Phenotype frequency and genotype frequency
Do the following examples describe directional, disruptive, balancing, or stabilizing selection? c. Birth weight in humans
Stabilizing. Low birth weight is selected against because it results in low survival. Also, very high birth weight is selected against because it could cause problems in delivery, which also could decrease the survival rate.
What is the functional significance of sticky ends in a cloning experiment? What type of bonding makes the ends sticky?
Sticky ends, which are complementary in their DNA sequence, promote the binding of DNA fragments to each other. This binding is due to hydrogen bonding between the sticky ends. Remember that AT base pairs form two hydrogen bonds, while GC base pairs form three hydrogen bonds.
Two populations of antelope are separated by a mountain range. The antelope are known to occasionally migrate from one population to the other. Migration can occur in either direction. Explain how migration affects the following phenomena: b. Allele frequencies in the two populations
The allele frequencies between the two populations will tend to be similar to each other, due to the intermixing of their alleles.
What is the intuitive meaning of the mean fitness of a population? How does its value change in response to natural selection?
The intuitive meaning of the mean fitness of a population is the relative likelihood that members of a population will reproduce, that is how well the population as a whole is adapted to its present environment. If the mean fitness is high, it is likely that an average member will survive and produce offspring. Natural selection increases the mean fitness of a population
Discuss the advantages of next-generation sequencing technologies.
The overall advantage of next- generation sequencing is that a large amount of DNA sequence can be obtained in a short period of time, and at a lower cost. One common innovation is that the need to subclone fragments of DNA into vectors is no longer necessary. Also, some of the methods involve the parallel analysis of an enormous number of samples simultaneously.
.Explain the basis for using an antibody as a probe in a Western blotting experiment.
The products of protein-encoding genes are proteins with a particular amino acid sequence. Antibodies can specifically recognize proteins due to their amino acid sequence. Therefore, an antibody can detect whether or not a cell is making a particular type of protein.
What is the purpose of a Northern blotting experiment? What types of information can it tell you about the transcription of a gene?
The purpose of a Northern blotting experiment is to identify a specific RNA within a mixture of many RNA molecules, using a fragment of cloned DNA as a probe. It can tell you if a gene is transcribed in a particular cell or at a particular stage of development. It can also tell you if premRNA is alternatively spliced into two or more mRNAs of different sizes.
In Southern, Northern, and Western blotting, what is the purpose of gel electrophoresis?
The purpose of gel electrophoresis is to separate the many DNA fragments, RNA molecules, or proteins that were obtained from the sample you want to probe. This separation is based on molecular mass and allows you to identify the molecular mass of the DNA fragment, RNA molecule, or protein that is being recognized by the probe.
What is cDNA? In eukaryotes, how does CDNA differ from genomic DNA?
The term CDNA refers to DNA that is made using RNA as the starting material. Compared to genomic DNA, it lacks introns.
Discuss the the reasons reasone why the proteome is larger than the genome of a given species.
There are two main reasons why the proteome is larger than the genome. The first reason involves the processing of pre-MRNA, a phenomenon that occurs primarily in eukaryotic species. RNA splicing and editing can alter the codon sequence of MRNA and thereby produce alternative forms of proteins that have different amino acid sequences. The second reason for protein diversity is posttranslational modifications. There are many ways that a given protein's structure can be covalently modified by cellular enzymes. These include proteolytic processing, disulfide bond formation, glycosylation, attachment of lipids, phosphorylation, methylation, and acetylation, to name a few.
In an in situ hybridization experiment, what is the relationship between the base sequence of the probe DNA and the site on the chromosomal DNA where the probe binds?
They are complementary to each other.
Which of the following statements are true about molecular markers? E. An STS is a molecular marker
True
Which of the following statements are true about molecular markers? b. A molecular marker is a segment of DNA that is found at a specific location in a genome.
True
Which of the following statements are true about molecular markers? d. We can follow the transmission of molecular markers using molecular techniques such as gel electrophoresis.
True
With regard to genetic drift, are the following statements true or false? If a statement is false, explain why. b. When a new mutation occurs within a population, genetic drift is more likely to cause the loss of the new allele rather than the fixation of the new allele.
True
With regard to genetic drift, are the following statements true or false? If a statement is false, explain why. a. Over the long run, genetic drift leads to allele fixation or loss.
True
With regard to genetic drift, are the following statements true or false? If a statement is false, explain why. d. Genetic drift is more significant in small populations.
True
The term polymorphism can refer to both genes and traits. a. Explain the meaning of a polymorphic gene and a polymorphic trait.
When a trait is polymorphic, this means that different individuals show phenotypic variation with regard to the trait. For example, petunias can have red or white flowers. Flower color is polymorphic in petunias. When a gene is polymorphic, it exists in two or more alleles. At the molecular level, alleles of a given gene have different DNA sequences. These differences could be very slight (e.g., a single-base change) or they could involve significant additions or deletions. Different alleles may cause differences in phenotype. For example, in Mendel's pea plants, the T allele resulted in tall plants, while the t allele caused dwarf plants.
When two populations frequently intermix due to migration, what are the long-term consequences with regard to allele frequencies and genetic variation?
When two populations intermix, both populations tend to have more genetic variation because each population introduces new alleles into the other population. In addition, the two populations tend to have similar allele frequencies, particularly when a large proportion migrates.
For each of the following, decide if it could be appropriately described as a genome: a. The E. coli chromosome
Yes
For each of the following, decide if it could be appropriately described as a genome: c. A complete set of 10 chromosomes in corn
Yes
For each of the following, decide if it could be appropriately described as a genome: d. A copy of the single-stranded RNA packaged into human immunodeficiency virus (HIV)
Yes
A person with a rare genetic disease has a sample of her chromosomes subjected to fluorescence in situ hybridization using a probe that is known to recognize band p11 on chromosome 7. Even though her chromosomes look cytologically normal, the probe does not bind to this person's chromosomes. How would you explain these results? How would you use this information to positionally clone the gene that is related to this disease?
You would conclude that she has a deletion of the gene that the probe recognizes. To clone this gene, you could begin with a marker that is known to be near band p11 and walk in either direction. This walking experiment would be done on the DNA from a unaffected person and compared to the DNA from the person described in the problem. At some point, the walk would yield a clone that contained a deletion in the person with the disease, but the DNA would be present in an unaffected person. This DNA fragment in the unaffected person should also hybridize to the probe.
Gene polymorphisms can be detected using a variety of cellular and molecular techniques. Which techniques would you use to detect gene polymorphisms at the following levels? a. DNA level
____level, a clear-cut way to determine genetic variation is to clone and sequence genes. If the same gene is cloned from two different individuals and the sequences are different, this shows that there is genetic variation. In addition, several other methods can be used to detect genetic variation. For example, a comparison of Southern blots using samples from different individuals might reveal that a gene exists in different sizes or that it contains different restriction sites.
With regard to DNA microarrays, answer the following questions: a. What is attached to the slide? Be specific about the number of spots, the lengths of DNA fragments, and the origin of the DNA fragments.
a. A DNA microarray is a small slide that is dotted with many different fragments of DNA. In some microarrays, DNA fragments, which were made synthetically (e.g., by PCR), are individually spotted onto the slide. The DNA fragments are typically 500 to 5,000 bp in length, and a few thousand to tens of thousands are spotted to make a single array. Alternatively, short oligonucleotides can be directly synthesized on the surface of the slide. In this process, the DNA sequence at a given spot is produced by selectively controlling the growth of the oligonucleotide using narrow beams of light. In this case, there can be hundreds of thousands of different spots on a single array.
In a donor population, the allele frequencies for the common (HbA) and sickle cell alleles (HbS ) are 0.9 and 0.1, respectively. A group of 550 individuals migrates to a new population containing 10,000 individuals; in the recipient population, the allele frequencies are HbA = 0.99 and HbS = 0.01.
a. Calculate the allele frequencies in the conglomerate population. A. ApC = m(pD- pR) With regard to the sickle-cell allele: ApC = (550/10,550)(0.1-0.01) = 0.0047 pC = pR + ApC = 0.01 + 0.0047 = 0.0147 B. C. b. Assuming the donor and recipient populations are each in Hardy-Weinberg equilibrium, calculate the genotype frequencies in the conglomerate population prior to further mating between the donor and recipient populations. We need to calculate the genotypes separately: For the 550 migrating individuals, HBAHBA = (0.9)2 = 0.81, or 81% We expect (0.81)550 = 445.5 HBAHBS = 2(0.9)(0.1) = 0.18 We expect (0.18)550 = 99 HbSHbS = (0.1)2 = 0.01 We expect (0.01)550 = 5.5 For the original recipient population, HBAHBA = (0.99)2 = 0.98 We expect 9,801 individuals to have this genotype HBAHBS = 2(0.99)(0.01) = 0.0198 We expect 198 with this genotype H%SHBS = (0.01) 2 = 0.0001 We expect 1 with this genotype To calculate the overall population: (445.5 +9801)/10,550 = 0.971 HBAHBA homozygotes (99 + 198)/10,550 = 0.028 heterozygotes (5.5 + 1)/10,550 = 0.00062 HBSHBS homozygotes c. What will be the genotype frequencies of the conglomerate population in the next generation, assuming it achieves Hardy-Weinberg equilibrium in one generation? After one round of mating, the allele frequencies in the conglomerate (calculated in part A), should yield the expected genotype frequencies according to the Hardy-Weinberg equilibrium. Allele frequency of HbS = 0.0147, so HbA = 0.985 HBAHBA = (0.985)2 = 0.97 HBAHBS = 2(0.985) (0.0147) = 0.029 HBSHBS (0.0147)2 = 0.0002
We are now in the age of omics'. Predict what the following terms seek to characterize: a. Metabolomics -
all of the metabolites (small molecules) in a sample at one time
We are now in the age of omics'. Predict what the following terms seek to characterize: c. Lipidomics -
identifying all lipid species in a sample
We are now in the age of omics'. Predict what the following terms seek to characterize: d. Neurogenomics -
the genes/mRNAS that contribute to neural function.
Predict what the following terms seek to characterize: b. Microbiomics-
the study of all the microbes in a sample at one time (similar to metagenomics, but just focusing on microbiome of an individual)