Exam 19: Developmental Genetics

Once a chromosomal position for a putative gene associated with Parkinson disease is verified, which of the following is a next step?

If the odds ratio for a particular QTL/DNA marker pair is 2.2, this indicates that the organism is how many times more likely to get Q10M10 gametes?

After successful QTL mapping, ___________ lines, which result from the repeatedly backcrossing to form highly inbred lines, can help identify QTL genes.

Which component of variance in a trait such as stamina in horses is the best indicator of whether the trait will respond to selection?

A scientist is researching oil content of seeds from a new plant species named R. tificial. The average oil content from plants in her lab population is 52%, and she has determined the narrow sense heritability (h²) is 0.60. If she randomly mates individuals with 70%, 71%, 72%, 73%, and 74% seed oil content what is the expected response to selection (R)?

Which of the following is true?

Genetic variance can be partitioned into which three types of variance?

Parkinson disease (PD) is a neurodegenerative disease that has been associated with a significant number of different genes, therefore showing it to be genetically heterogenic. One recent study in 278 families found evidence of two such possible loci. Evidence for linkage to chromosome 18q11 was presented by Gao et al. in 2009. Which of the following would be considered reputable evidence for this?

What is the mean, variance (s²), and standard deviation (s) of the following sample: 1.00, 2.00, 3.00, 5.00, 7.00, 9.00, 10.00, and 11.00.

An animal breeder asks your advice about which, of a number of traits, could most effectively be selected for in his herd. A trait with which of the following would you most correctly suggest?

In a newly discovered diploid animal species, tail length is determined solely by 2 additive gene loci that can have the allele s, which contributes 4mm, and the allele l, which contributes 15mm. Two lines with the genotypes AsAsBsBs and AlAlBsBs are mated to create the F₁ generation. a. What is the predicted genotype and phenotype of the F₁ progeny? b. If two individuals from the F₁ generation are crossed, each phenotypic category will occur in what proportion?

What two measures describe the distribution of a trait in a sample?

A scientist is researching oil content of seeds from a new plant species named R. tificial. She has determined the narrow sense heritability (h²) is 0.80. She mates plants with an average seed oil content of 32%. If the response to selection (R) was 16%, what is the estimated average oil content of seeds in the entire lab population?

A hypothetical condition in some domesticated fowl is identified phenotypically by patchy loss of feathers on the animals' backs. Although several factors, genetic and environmental, are found to be involved, only about 3% of any population with any of these factors are found with feather loss. Which of the following is a likely cause?

While most additive polygenic traits show continuous distribution, some can be divided into two or more categories based on their contribution to genetic liability. Such traits are said to have what separation between affected and unaffected members of a population?

If a trait results from genetic variation as well as environmental factors, it is known as a_______trait.

The part of the genetic variance that is attributed to epistatic interactions is called the_________variance.

How many distinct phenotypic categories should be observed for a polygenic trait in humans that results from segregation of additive alleles for 10 genes?

Given a list of concordances (as percentages) for monozygotic and dizygotic twins for a selection of traits, describe how you would evaluate the relative input of environmental versus genetic factors for each trait.

Recent work in Drosophila demonstrated that the genes known as the chromatin remodeling complex co- localize at loci for hsp genes that respond to heat shock. Outline a procedure you could use to substantiate this finding.