In mice, dwarfism is caused by an X-linked recessive allele, and pink coat is caused by an autosomal dominant allele (coats are normally brownish). If a dwarf female from a pure line is crossed with a pink male from a pure line, what will be the phenotypic ratios in the F1 and F2 in each sex? (Invent and define your own gene symbols.)

The accompanying pedigree shows the pattern of transmission of two rare human phenotypes: cataract and pituitary dwarfism. Family members with cataract are shown with a solid left half of the symbol; those with pituitary dwarfism are indicated by a solid right half. a.What is the most likely mode of inheritance of each of these phenotypes? Explain.
b.List the genotypes of all members in generation III as far as possible.
c. If a hypothetical mating took place between IV-1 and IV-5, what is the probability of the first child’s being a dwarf with cataracts? A phenotypically normal child?