Question

2o poihe Some cats have hairs in which there is more than one hair distributed along the hair shaft. This is known agouti. The agouti hairs are produced by protein which is coded for by the agouti gene. a. The agouti gene has two allles. The dominantallele codes for agouti hairs and the recessive allele codes for non-agouti hairs. State the phenotypes that are possible and the probability of having an offspring with each phenotype for a cross between a heterorygous Agouti female and a non-agouti male b. The length of cat hair is controlled by one gene with two allieles. The L allele codes for short hair and the I allele codes for long hair. Using the information on agouti hair color from problem "a, state the phenotypes that are possible and the probability of having an offspring with each phenotype for a cross between a long-haired, heterozygous Agouti female and a heterozysous short-haired, non-agouti male. c. Cats have a gene known as the white masking gene, which has 2 alleles. The W allele produces a protein that prevents the production of pigment producing cells. The w allele produces a protein that results in normal production of pigment producing cells. The WW and Ww genotypes produce white cats no matter what other color genes they carry. Only ww cats will express their normal pigmentation. Using the information from problem "b", state the phenotypes that are possible and the probability of having an offspring with each phenotype for a cross between a long-haired heterozygous Agouti female cat that is homozygous recessive for the white masking gene and a male cat that is non-agouti, heterozygous for the short-haired gene, and heterozygous for the white masking gene

Answer 1

a.

Heterozygous agouti female (Aa) crossed with non-agouti male (aa)

	A	a
a	Aa	aa
a	Aa	aa

possible phenotypes = Agouti and non-agouti

probability of having an Agouti as well as non-agouti offspring is 0.5.

b.

Cross between long haired Heterozygous agouti female (llAa) and heterozygous short haired non-agouti male (Llaa).

	lA	la
La	LlAa	Llaa
la	llAa	llaa

probability

possible phenotypes - LlAa (short hair, agouti) 1/4

Llaa - short hair, non-agouti 1/4

llAa - long hair, agouti 1/4

llaa - long hair, non-agouti 1/4

c.

Cross between long haired heterozygous agouti female that is homozygous recessive for white masking gene (llAaww) and non-agouti male heterozygous for short haired gene and the white masking gene (aaLlWw)

	aLW	alW	aLw	alw
Alw	AaLlWw	AallWw	AaLlww	Aallww
alw	aaLlWw	aallWw	aaLlww	aallww

Possibile phenotypes probability

AaLlWw - agouti, short hair, white 1/8

AallWw - agouti, long hair, white 1/8

AaLlww - agouti, short hair, normal pigmented   1/8

Aallww - agouti, long hair, normal pigmented 1/8

aaLlWw - non agouti, shorrt hair, white 1/8

aallWw - non agouti, long hair, white   1/8

aaLlww - non agouti, short hair, normal pigmented 1/8

aallww - non agouti,long hair, normal pigmented   1/8