This pedigree is of a rare trait, in which children have extra fingers and toes. Which one of the following patterns of inheritance is consistent with this pedigree?

Question

This pedigree is of a rare trait, in which children have extra fingers and toes. Which one of the following patterns of inheritance is consistent with this pedigree? (A) Autosomal recessive (B) Autosomal dominant (C) Y-linkage (D) Sex linked recessive

Tardigrade Admin · Accepted Answer

Y-linked disorders are caused by mutations on the Y-chromosome. Because males inherit a Y-chromosome from their fathers, every son of an affected father will be affected. Because females inherit an X-chromosome from their fathers, female offspring of affected fathers are never affected.

Q. This pedigree is of a rare trait, in which children have extra fingers and toes. Which one of the following patterns of inheritance is consistent with this pedigree?

Autosomal recessive

Autosomal dominant

Y-linkage

Sex linked recessive

$Y$ -linked disorders are caused by mutations on the $Y$ -chromosome. Because males inherit a $Y$ -chromosome from their fathers, every son of an affected father will be affected. Because females inherit an $X$ -chromosome from their fathers, female offspring of affected fathers are never affected.