1) Joe's grandfather (on his mothers side) was a lizard man on a circus sideshow  (the result of rare X-linked recessive allele that gave him a tail). Joe meets and marries Julie, whose uncle on her mothers side had a tail removed at the age of 2.  Julie is now pregnant with their first child

a) Assign genotypes.

b) What is the probability that their first child will have a tail?

c) If the first child does have a tail, what is the probability that a second child will have a tail?                                             

2) Achondroplasia (dwarfism) is an autosomal dominant disorder, where individuals homozygous for the mutant allele do not survive

a) if a woman with achondroplasia marries a man of normal height, what proportion of their offspring is expected have achondroplasia?

b) if a woman with achrondroplasia marries a man with achondroplasia , what proportion of their offspring is expected to have achondroplasia?