When an organism has more than 10 fingers or toes, the condition is known as polydactylism. although polydactylism is rare, it is a dominant trait. if two cats that are heterozygous for polydactylism mate and have a litter with a total of 12 kittens, how many of them would you expect to have more than 10 fingers or toes?
If we say that heterozygous cat has a phenotype Aa for the polydactyl gene locus then : F1: Aa x Aa F2: AA Aa Aa aa This means that the proportion is 3:1 for the polydactyly phenotype (only aa is recessive and does not have polydactyly). Of the total 12 kittens, 9 will have polydactyly and 3 won’t.
