Genotype of male =AaBbXXhY Number of gametes =2n Where n= no. of heterozygous alleles (genes A, B, sex chromosome) Thus, Number of gametes =(2)3=8 The gametes produced wil be =abXh, abY,ABXh,aBY,aBXh,AbY,ABY and AbXh. Hence, number of sperm carrying abh=1/8.