The Fragile X Society

We are the UK registered charity providing support, information and friendship to families whose children and relatives have fragile X syndrome. We are also here to help the many professionals who are working and caring for children and adults affected by fragile X.

Fragile X Syndrome (FXS) is a genetic condition, affecting around 1 in 4000 males and 1 in 6000 females. It can cause a wide range of difficulties with learning, as well as social, language, attentional, emotional, and behavioural problems. Some may experience connective tissue issues such as difficulty breast-feeding, hypotonia, hyperflexibility, flat feet, recurrent ear infections and mitral valve prolapse. FXS is the most common inherited cause of learning disability.

Page reviewed 06.08.25