Question

Although the vast majority of women who inherit a single copy of an X-linked recessive disease allele are not affected by the disorder, a small percentage of women do display the disease phenotype. Which of the following could explain this rare phenomenon?

Answer can be more than one

A. X-inactivation that favors inactivation of the normal X chromosome
B. incomplete penetrance of the X-linked recessive allele
C. Turner syndrome (a sex-chromosome aneuploidy in which women have only one X chromosome)
D. multiple alleles of the X-linked recessive trait

Answer 1

Answer:

A and C

Explanation:

X-linked recessive diseases are disorders caused by a mutation on the X chromosome causes the phenotypic expression in males and only when it is homozygous for females.

A small percentage of women can display the disease phenotype on rare phenomenon such as;

• X-inactivation that favors inactivation of the normal X chromosome  
• Turner syndrome (a sex-chromosome aneuploidy in which women have only one X chromosome)