What is the chance, a female with the premutation or full mutation, will pass the Fragile X gene mutation to their children?

Since a woman has two X chromosomes, a woman with a premutation or full mutation has a 50% chance of passing on the X with the mutation in each pregnancy, and a 50% chance of passing on her normal X.

• If she has a premutation, and it is passed on (to either males or females), it can remain a premutation or it can expand to a full mutation.
• If she has a full mutation and it is passed on (to either males or females), it will remain a full mutation.

We recommend you work with a genetic counselor and your healthcare provider to review inheritance patterns.

To learn more:

• Genetics & Inheritance 
• Reproductive Options