Question

1)

Coat color in mice is determined by several independently assorting autosomal genes.

Gene A is involved in the distribution of pigment along the hair. A dominant allele (A) produces a hair color called "agouti"--the hair has dark pigment at the base and tip of each hair shaft and yellow pigment in the central portion of the shaft. Homozygous recessive mice (aa) are missing the yellow stripe and thus have solid dark-colored hair.

Gene B is involved in the color of the dark pigment. A dominant allele (B) produces black pigment. Homozygous recessive mice (bb) have brown/chocolate-colored hair.

Gene C is involved in the production of all pigments. If a dominant allele (C) is present, genes A and B produce pigment. Homozygous recessive mice (cc) are albino.

If you cross two mice that are heterozygous for all three genes, what distribution of coat colors would you expect?

Rank the following coat colors from most likely to least likely in the offspring.

1st choice black agouti
2nd choice brown agouti
3rd choice solid black
4th choice solid brown
5th choice albino

2)

Coat color in mice is determined by several independently assorting autosomal genes.

Gene A is involved in the distribution of pigment along the hair. A dominant allele (A) produces a hair color called "agouti"--the hair has dark pigment at the base and tip of each hair shaft and yellow pigment in the central portion of the shaft. Homozygous recessive mice (aa) are missing the yellow stripe and thus have solid dark-colored hair.

Gene B is involved in the color of the dark pigment. A dominant allele (B) produces black pigment. Homozygous recessive mice (bb) have brown/chocolate-colored hair.

Gene C is involved in the production of all pigments. If a dominant allele (C) is present, genes A and B produce pigment. Homozygous recessive mice (cc) are albino.

During cage cleaning weeks ago, your technician accidentally put some mice into the wrong cages. You find a black agouti female in a cage with an albino male. Breeding these two mice for several litters produced the following offspring:

• 16 albino
• 6 black agouti
• 6 brown agouti
• 2 black solid
• 2 brown solid

Given this data, can you identify the possible genotype(s) of the black agouti female parent?

3)

Coat color in mice is determined by several independently assorting autosomal genes.

Gene A is involved in the distribution of pigment along the hair. A dominant allele (A) produces a hair color called "agouti"--the hair has dark pigment at the base and tip of each hair shaft and yellow pigment in the central portion of the shaft. Homozygous recessive mice (aa) are missing the yellow stripe and thus have solid dark-colored hair.

Gene B is involved in the color of the dark pigment. A dominant allele (B) produces black pigment. Homozygous recessive mice (bb) have brown/chocolate-colored hair.

Gene C is involved in the production of all pigments. If a dominant allele (C) is present, genes A and B produce pigment. Homozygous recessive mice (cc) are albino.

During cage cleaning weeks ago, your technician accidentallly put some mice into the wrong cages. You find a black agouti female in a cage with an albino male. Breeding these two mice for several litters produced the following offspring:

• 16 albino
• 6 black agouti
• 6 brown agouti
• 2 black solid
• 2 brown solid

Given this data, can you identify the possible genotype(s) of the albino male parent?

4)

Coat color in mice is determined by several independently assorting autosomal genes.

Gene A is involved in the distribution of pigment along the hair. A dominant allele (A) produces a hair color called "agouti"--the hair has dark pigment at the base and tip of each hair shaft and yellow pigment in the central portion of the shaft. Homozygous recessive mice (aa) are missing the yellow stripe and thus have solid dark-colored hair.

Gene B is involved in the color of the dark pigment. A dominant allele (B) produces black pigment. Homozygous recessive mice (bb) have brown/chocolate-colored hair.

Gene C is involved in the production of all pigments. If a dominant allele (C) is present, genes A and B produce pigment. Homozygous recessive mice (cc) are albino.

During cage cleaning weeks ago, your technician accidentally put some mice into the wrong cages. You find a black agouti female in a cage with an albino male. Breeding these two mice for several litters produced the following offspring:

• 16 albino
• 6 black agouti
• 6 brown agouti
• 2 black solid
• 2 brown solid

What proportion of the agouti offspring would you expect to be homozygous for Gene A (genotype AA)?

5)

Coat color in mice is determined by several independently assorting autosomal genes.

Gene A is involved in the distribution of pigment along the hair. A dominant allele (A) produces a hair color called "agouti"--the hair has dark pigment at the base and tip of each hair shaft and yellow pigment in the central portion of the shaft. Homozygous recessive mice (aa) are missing the yellow stripe and thus have solid dark-colored hair.

Gene B is involved in the color of the dark pigment. A dominant allele (B) produces black pigment. Homozygous recessive mice (bb) have brown/chocolate-colored hair.

Gene C is involved in the production of all pigments. If a dominant allele (C) is present, genes A and B produce pigment. Homozygous recessive mice (cc) are albino.

During cage cleaning weeks ago, your technician accidentally put some mice into the wrong cages. You find a black agouti female in a cage with an albino male. Breeding these two mice for several litters produced the following offspring:

• 16 albino
• 6 black agouti
• 6 brown agouti
• 2 black solid
• 2 brown solid

How many of the albino offspring have the genotype for brown color (bb)?