Do males and females have the same symptoms for Fragile X?

Though Fragile X syndrome (FXS) occurs in both genders, males are more frequently affected than females, and generally with greater severity. 

• Males (XY) — having only one X chromosome — will develop Fragile X syndrome because they have a mutation of their single (only) X chromosome.
• Females (XX) — having two X chromosomes — can have the unaffected X reduce the effects of the affected X, which typically leads to no or milder symptoms of Fragile X syndrome. (This is an important distinction, as many females with the full mutation do not consider themselves, nor are they considered by others, to “have” Fragile X Syndrome.)

Learn more:

• Request our free e-book, Fragile X 101  
• What is Fragile X syndrome?  
• Fragile X Info Series: Fragile X Syndrome An Overview for Families and Providers  
• The Unique Challenges for Females with Fragile X Syndrome
• Fragile X Info Series: Females and Fragile X
• Genetics & Inheritance