A certain dominant gene causes some people in the population to be born with 6 fingers (F) instead of 5 (f). Another dominant gene causes dwarfism (D) while normal height (d) is recessive. A father, Barry, has six fingers and has dwarfism (he is heterozygous for both traits). The mother, Jill, has 5 fingers and is also a dwarf. Jill's father, Sam, is of normal height. What percent/ratio of the offspring will be heterozygous for both traits? 9/163/41/43/161/2 Please review: The genotypes of Barry and Jill are: FfDd xffDd Either divide the crosses into monohybrids (e.g. Ff x ff and Dd xDd ) and find the probabilities in each case of being heterozygous Or you can do a Punnett square. First, find the gametes and then set up the cross..