Exam 19: Developmental Genetics

In some traits, different phenotypes result from genes whose alleles each contribute a specific increment to the whole. The phenotypes then have a ________phenotypic distribution.

After locating a genome region likely to include a QTL, what must be found in this region?

Which will exhibit the most shared maternal effects (uterine environment, etc.), identical or fraternal twins?

In a newly discovered diploid animal species, tail length is determined solely by 3 additive gene loci that can have the allele s, which contributes 4mm, and the allele l, which contributes 15mm. Two lines with the genotypes AsAsBsBsClCl and AlAlBsBsCsCs 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?

Calculate the narrow sense heritability (h2) for the following data on a trait in turkeys: VA = 11.0 VE = 94.4 VP = 114.2 VD = 13.8

Which of the following is FALSE regarding human multifactorial traits?

A group is experimenting with selection in an insect species due to exposure to a newly developed insecticide, cpd AW143. The group has found that after 10 generations of exposure, the population is now bimodal in its response to the drug. Close to 30% of the population are completely normal while 70% live only about 1/6 of the normal lifetime. This is an example of ______.

Which of these statements about heritability is FALSE?

What is the statistically acceptable lod score that provides evidence of genetic linkage?

QTLs are most often mapped relative to DNA markers by using what scores as measurement?

Mean platelet volume (MPV) in humans increases with heart attacks and strokes and is used to predict recurrence as well as mortality. MPV has high heritability. A recent GWA study found MPV to be associated with SNPs on chromosomes 12, 3, and 17, respectively. These three QTLs accounted for 4- 5% of MPV variance. Which of the following is a reasonable explanation?

Although no specific gene alteration has yet been demonstrated as a cause for schizophrenia (SZ), it is known to have a strong genetic component. A recent study has found a strong association between SZ and a locus at chromosome 10q22- 23 in Ashkenazi Jewish and Taiwanese Han populations. Which of the following is probable?

It is clearly established that obesity has greatly increased in children over the last several decades in the United States. While several genes have been identified that increase the potential for obesity, environmental influences are also involved. Which of the following is most likely?