Fragile X syndrome occurs:
A)more often in males than in females.
B)only in females.
C)in both sexes equally.
D)only in males.

Question

Quizplus · Accepted Answer

Fragile X syndrome is caused by a mutation on the X chromosome, so males, who only have one X chromosome, are more likely to be affected than females, who have two X chromosomes. However, females can also be affected if they have the mutation on both X chromosomes or if their X chromosome carrying the mutation is deactivated or "turned off."

Fragile X Syndrome Occurs