Answer to Question #333512 in Genetics for mae

Question

 Instruction: Analyze each genetic problem. Answer what is asked for. Show complete solution.

1. A cross between a black cat and a tan cat results in a tabby A tabby cat is crossed with a tan cat.

• What is the pattern of inheritance in this example? (1 point)
• What ratio of the offspring will have tabby fur? Tan fur? Black fur? (3 points answer; 4 points Punnett square)

1. In the n the early 1940s, famed entertainer Charlie Chaplin was taken to court in a paternity case brought by his former protege, Joan Berry. Berry was 23 and Chaplin 54, and she alleged that he was the father of her newborn baby, Carol Ann. Charlie Chaplin’s blood type was already on record as type AB. The mother of the child had type A and her child had type O

• Complete a Punnett square for the possible cross of Charlie and the (4 points)
• The judge ruled in favor of the mother and ordered Charlie Chaplin to pay child support costs of the child. Was the judge correct in his decision based on blood typing evidence? Explain why or why (3 points)

Answer 1

1) Let the gene that is responsible for the color in cats be A. Judging by the cross described above, gene A is codominant. Such a cross in the genetic aspect will look like this:

AA (black) × aa (tan)

↓

4 Aa (tabby)

Aa (tabby) × aa (tan)

↓

2 Aa (tabby) + 2 aa (tan)

• The pattern of inheritance is autosomal codominant.
• When a tabby cat is crossed with a tan cat, the offspring will be tabby in 50% of cases, and in another 50% of cases it will be tan. There will be no black cats in this litter.

The Punnett square by crossing a tabby cat with a tan cat will look like this:

2) The AB blood type corresponds to the I^AI^B genotype, the O blood type corresponds to the I^OI^O, and the A blood type corresponds to the I^AI^A or I^AI^O. Let's assume that Joan Berry has the I^AI^O genotype, in which there is an I^O allele to construct the I^OI^O genotype in the future. Therefore, the cross will be as follows:

I^AI^O (Joan Berry) × I^AI^B (Charlie Chaplin)

↓

• The judge, of course, was not right, since Carol Ann cannot be the biological daughter of Charlie Chaplin, since the birth of a child with the I^OI^O genotype is impossible in parents, one of which has the I^AI^B genotype.