Concept explainers
You picked up two mice (one female and one male) that had escaped from experimental cages in the animal facility. One mouse is yellow in color, and the other is brown agouti. (Agouti hairs have bands of yellow, while non-agouti hairs are solid-colored.) You know that this mouse colony has animals with different alleles at only three coat color genes: the agouti (A) or non-agouti (a) or yellow (A ) alleles of the A gene (A > A > a; A is a recessive lethal), the black (B) or brown (b) alleles of the B gene (B > b), and the albino (c) or non-albino (C) alleles of the C gene (C > c; cc is epistatic to all other
a. | What alleles of the A, B, and C genes are present in the two mice you caught? |
b. | After raising several litters from these two parents, you have many offspring. How many different coat color phenotypes (in total) do you expect to see expressed in the population of offspring? What are the phenotypes and corresponding genotypes? |
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ND STONY BROOK UNIVERSITY LOOSELEAF GENETICS: FROM GENES TO GENOMES
- Your internship with Dr. Nefario at Gru Industries is going well so far, but a recent mission to obtain a shrink ray requires a special kind of Minion. You identify that the ideal Minion phenotypes for this mission are two eyes, pale yellow, and short. From your previous work, you’ve found that:Two-eyed (D) is completely dominant over one-eyed (d)Yellow (Y) is incompletely dominant with white (y)Tall (T) is completely dominant over short (t) a. The only reproductive individuals you have at the moment (it was surprise mission!) are a true breeding two-eyed, yellow, short Minion and a one heterozygous for each trait. What genotypic ratios would you expect for this crossassuming that each locus is on a different chromosome? What total proportion would you expect to be the desired phenotype for the mission? b. The mission has since been delayed due to lack of financial support, so you’ve got some time. All the individuals from the F1 cross above are now reproductive. Which genotypes would…arrow_forwardSuppose that you are studying the role of Protein B, which you believe plays a role in regulating PCD/Apoptosis in mice. You create two lines of mutant mice. One (bb) is homozygous for a loss-of-function allele of gene B. The other (Bb) is heterozygous, with one wild-type allele and one loss-of function allele. Initially you pay particular attention to two phenotypes of the resulting mice:(i) The morphology of their paws (see picture) (ii) The size of their brains & shape of their skulls. The bb mice have unusually large brains and unusual protrusions from their skulls. Based on these data, does it appear that Protein B, when present and active, favors or inhibits PCD/Apoptosis?Briefly explain your reasoning. The answer should address both the paw and brain/skull data.arrow_forwardSuppose that you are studying the role of Protein B, which you believe plays a role in regulating PCD/Apoptosis in mice. You create two lines of mutant mice. One (bb) is homozygous for a loss-of-function allele of gene B. The other (Bb) is heterozygous, with one wild-type allele and one loss-of function allele. Initially you pay particular attention to two phenotypes of the resulting mice:(i) The morphology of their paws (see picture)(ii) The size of their brains & shape of their skulls. The bb mice have unusually large brains and unusual protrusions from their skulls. Suggest one other aspect of mouse morphology or physiology that you might expect to be altered in the absence of Protein B. Briefly explain your reasoning. Also, based on the apparent effect of Protein B on the likelihood of PCD/Apoptosis, would you classify Protein B as the product of a proto-oncogene or of a tumor suppressor gene?arrow_forward
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