Fragile X-associated disorders (FXD) is a family of genetic conditions that can affect individuals in a variety of ways. The conditions are all caused by changes in the gene known as FMR1. Fragile X Syndrome (FXS) is caused by a full mutation of the FMR1 gene. Fragile X-associated tremor/ataxia syndrome (FXTAS) and Fragile X-associated primary ovarian insufficiency (FXPOI) are caused by a premutation of the FMR1 gene and Fragile X-Neuropsychiatric Disorders (FXAND).
Fragile X-associated primary ovarian insufficiency (FXPOI)
FXPOI is a genetic condition caused by a premutation of the FMR1 gene. “Primary ovarian insufficiency” refers to a spectrum of impaired ovarian function that includes infertility and early menopause in women prior to the age of 40 years. Learn more about FXPOI here.
Fragile X-associated tremor/ataxia syndrome (FXTAS)
FXTAS is a genetic condition that affects some older premutation carriers of the FMR1 gene change. Symptoms include balance, tremor, and memory problems and usually occurs after age 50, with symptoms worsening with age. It affects more males than females. Learn more about FXTAS here.
Fragile X-Associated Neuropsychiatric Disorders (FXAND)
FXAND was first discussed in 2018 by Dr. Randi Hagerman, medical director and developmental paediatrician at the UC Davis MIND Institute in California, in a published article in the scientific journal Frontiers in Psychiatry. Dr. Hagerman and her team describe anxiety, depression, attention deficit hyperactive disorder (ADHD), chronic pain, fibromyalgia, chronic fatigue, sleep disturbances, and autoimmune problems as potentially related to carrying a Fragile X premutation. They suggest that the identified toxic effect of the premutation on the brain may underlie these problems.
It is important to note that the symptoms described in Dr. Hagerman’s article are relatively common in the general population, and many individuals without Fragile X premutations are affected by these same medical and psychological problems. However previous research by her team and others have shown that these symptoms are more common in premutation carriers compared to those who are not carriers. Many carriers of a premutation do not experience any such symptoms while others experience several.
Download the Fragile X-Associated Neuropsychiatric Disorders (FXAND) paper here.