Chapter 24.2, Problem 2CYP

Summary Introduction

To describe:

The phenotypic ratio that is expected for a cross in which both parents have one X-linked recessive allele.

Introduction:

Male are hemizygous for X-linked genes (they have only one X chromosome) and any male with one copy of an X-linked recessive disease allele is affected. With both X and a Y-chromosomes, males inherit both X and Y-linked traits, while females only inherit X-linked traits. As the X-chromosome is larger and contains more genes than the Y-chromosome, most sex-linked traits are X-linked traits.