Pigment of chicken feathers is regulated by two genes, the gene for feather pigm
ID: 167197 • Letter: P
Question
Pigment of chicken feathers is regulated by two genes, the gene for feather pigment C, and a gene that inhibits pigment production, I. A mother chicken, who is heterozygous for gene c, and heterozygous for gene I, is crossed with a father chicken, who is homozygous recessive for the pigment gene, and heterozygous for gene I. Inhibition is dominant to uninhibited, pigmented feathers are dominant to un pigmented feathers. What are the potential genotypes of the gametes produced by the mother for these two genes? What are the potential genotypes of the gametes produced by the father for these two gametes? What is the probability of one of the offspring of these two chickens having pigmented feathers? In a population of 150 chickens, produced from the same parents, how many chickens would you expect to have white feathers?Explanation / Answer
Mother genotype is CcIi
Fathers genotype is ccIi
Inhibited> uninhibited
Pigmented feathers > unpigmented feathers
C is dominant over c
‘I’ is dominant over ‘i’
Cross between ccIi father X CcIi mother
Gametes cI ci CI Ci cI ci
Gamtes produced by female are CI Ci cI ci
Gametes produced by father cI ci
c) The probability of pigmentation is 6/8
CI ci CI CCII pigmented, Inhibited CcIi pigmented, inhibited Ci CCII pigmented, Inhibited Ccii pigmented, uninhibited cI CCII pigmented, Inhibited ccIi no pigment, inhibited ci CCII pigmented, Inhibited ccii no pigment, uninhibited