Problem set 2- Due in class Wednesday 9/22

1.  What are the blood types expected of children of parents with the 
following genotypes:
a. AB x O
b. BB x O
c. Ai x Bi
d. O x O

2.  What is the probability that a woman whose parents' blood types 
were AB and B will have children with blood type O if she marries 
a man with blood type A?

3.  In rabbits, C = agouti coat color, Cch = chinchilla, Ch = Himalayan 
and c = albino.  The four alleles constitute a multiple allelic series.  
The agouti C is dominant to the three other alleles, c is recessive to 
all three other alleles, and Chinchilla is dominant to Himalayan.  
Determine the phenotypes of progeny from the following crosses 
(slash marks have been put between alleles within an individual 
to make it easier to read):
a. C/C x c/c
b. C/Cch x C/c
c. C/c x C/c
d. C/Ch x Ch/c
e. C/Ch x c/c
f. Cch/Ch x Ch/c
g. Ch/c x c/c
h. C/Ch x c/c
i. C/Ch x C/Cch

4.  A Japanese strain of mice has a peculiar uncoordinated gait 
called waltzing, which is due to a recessive allele: v.  The dominant 
allele V causes mice to move in a coordinated fashion.  A mouse 
geneticist has recently isolated another recessive mutation that 
causes uncoordinated movement.  This mutation, called tango, 
could be an allele of the waltzing gene, or it could be a mutation 
in an entirely different gene.  Propose a test (a cross) to determine 
whether the waltzing and tango mutations are alleles.  

5.  A husband and wife have normal vision, although both of their 
fathers are red-green color-blind, which is inherited as an X-linked 
recessive condition.  What is the probability that their first child 
will be (a) A normal son?  (b) A normal daughter? (c) A color-blind 
son? (d) A color-blind daughter?

6.  With reference to Figure 4.14 in your book (the mouse coat 
color system), what F1 and F2 genotypic and phenotypic ratios 
are obtained from a cross between AABB and aabb mice?  In 
three crosses between agouti females whose genotypes were 
unknown and males of the aabb genotype, the following 
phenotypic ratios were obtained:

1:  8 agouti
     8 albino

2:  9 agouti
     10 black

3:  4 agouti
     5 black
    10 albino

What are the genotypes of these 3 female parents?

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