Assume that long ear lobes are an autosomal dominant trait t

Assume that long ear lobes are an autosomal dominant trait that exhibits 30% penetrance. A person heterozygous for long ear lobes mates with a person who is homozygous for normal ear lobes. What is the probability that their have long ear lobes? 50% 30% 15% 25% 35% If there are five alleles at a locus, how many different kinds of homozygotes will there be? 1 2 5 25 3125 In this chapter, we considered Joan Barry\'s paternity suit against Charlie Chaplin and how, on the basis of blood type could not have been the father of her child. Barry had blood type A, her child had blood type B, and Chaplin had blood type O. types are possible for the father of Barry\'s child? A only B only AB only A or B AB or B

Solution

Assume that long ear lobes in humans are an autosomal dominanttrait that exhibits 30% penetrance. A person who is heterozygousfor long ear lobes mates with a person who is homozygous for normalear lobes. What is the probability that their first child will havelong ear lobes?

probability of inheriting the dominant allele = 50%;

the probability of expressing it =30%.

The combined probability of both = 0.5(0.3) = 0.15, or

answer =15%

if there are five alllels at locus. How many different kinds of homozygous will there be

answer =5

number of genotypes = n(n+1)/2.

For five alleles (n = 5),

15 possible genotypes

answer= five homozygotes

1,1

1,2

2,2

1,3

2,3

3,3

1,4

2,4

3,4

4,4

1,5

2,5

3,5

4,5

5,5

In this chapter we discussed Joan Barry’s paternity suit against Charlie Chaplin and how, on the basis of blood types, Chaplin could not have been the father of her child.

(a) What blood types are possible for the father of Barry’s child?

        Answer

Since Barry’s child inherited an I^Ballele from the father, the father could have been B or AB.

(

1,1
1,2	2,2
1,3	2,3	3,3
1,4	2,4	3,4	4,4
1,5	2,5	3,5	4,5	5,5