What could be the genotype of the parents who have a. Two kids one of which is tongue roller and the bitter taster (homozygous for both traits) and the other is a non-roller and non-taster. Note, both abilities are dominant traits b. Two kids, both of which are non-rollers and non- tasters. Solution Answer: (a) Since one of the kids is a non-roller and non-taster (homozygous recessive, bbrr) and the other is homozygous dominant (BBRR), the genotypes of the parents should be heterozygous dominant (BbRr). Crossing BbRr * BbRr, we get (in F1) Proportion of BBRR = 1 / 16 and bbrr = 1 / 16 (b) Both the kids are non-rollers and non-tasters. So, both are homozygous recessive for the traits. The genotypes of each parents should contain atleast one recessive allele for each trait. Therefore, the genotype of the parents are: - b - r and - b - r.