Fragile X syndrome
A) is an example of polygenic inheritance.
B) occurs when there is a sudden but permanent change in a segment of DNA.
C) is the most common inherited cause of mental retardation.
D) occurs more often in females than males because the disorder is X-linked.

Question

Quizplus · Accepted Answer

Fragile X syndrome is the most common inherited cause of mental retardation, affecting both males and females. It is caused by a mutation in the FMR1 gene on the X chromosome.

Fragile X Syndrome