Question

Your BFF is a red-headed, left-handed, blue-eyed girl. She wants you to explain to her the genetic basis of her three

traits. So, your task is to provide her with the most up-to-date explanation, to the extent

that is possible.

Answer 1

red hair, left handed, and blue eyes are recessive traits.

Any trait has its two allele, dominant and recessive. Dominant trait allele if present with the recessive allele, then the phenotype will be of dominant allele.

Suppose A = dominant allele for brown color hair, a = recessive allele for red color hair.

As mentioned above red color hair is recessive in nature. for the recessive traits to show, the alleles should be recessive only.

Aa (brown hair) (parent 1) is crossed with Aa (parent 2) (brown hair). They both have gametes A and a.

Their children will have genotype AA, aa, and Aa. AA = brown color, aa = red color hair, and Aa= brown color hair.

Same case goes with the left hand and blue eyes traits.

So, the girl parents must be having recessive alleles for all the traits, and she must have inherited all the recessive allele only.