The expected proportions of phenotypes in children obtained from B B M M × B b M m , B b M m × B b M m , and B b M m × b b m m . Introduction: The hair color in humans is regulated by two interacting genes. The pigment melanin is present in both types of hair that is brown hair as well as blond hair, however, it is present more in brown-haired people. Blond hair ( b ) is recessive to brown hair ( B ) . The synthesis of melanin is coded by another gene having two alleles. The ( M ) allele allows the synthesis of melanin whereas the ( m ) allele prevents it. The genotype ( m m ) are albino.

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Chapter 11, Problem 5GP

a.

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To determine:

The expected proportions of phenotypes in children obtained from BBMM×BbMm, BbMm×BbMm, and BbMm×bbmm.

Introduction:

The hair color in humans is regulated by two interacting genes. The pigment melanin is present in both types of hair that is brown hair as well as blond hair, however, it is present more in brown-haired people. Blond hair (b) is recessive to brown hair (B). The synthesis of melanin is coded by another gene having two alleles. The (M) allele allows the synthesis of melanin whereas the (m) allele prevents it. The genotype (mm) are albino.

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