What Does NxGen MDx Screen For?
We screen for up to 120 genetic disorders that can affect your pregnancy, the health of your baby, and your family's future. You can learn more about our various screens — and which sets of screens (or "panels") align with where you are in your reproductive journey.
Fragile X and FMR1-Related Disorders
What Your Test Results Mean:
Fragile X Intermediate Carriers
Intermediate carriers are not at an increased risk to have a child with fragile X syndrome; however, your family members (siblings or offspring) may be at an increased risk to be premutation allele carriers of fragile X syndrome. Intermediate allele carriers do not have an increased risk for developing FMR1-related conditions.
Since this is an inherited gene change, this information may be helpful to share with family members as it may impact their family planning.
Fragile X Premutation Carriers
Premutation carriers are at an increased risk to have a child with fragile X syndrome. As a female carrier, there is a 50% chance that you will pass your premutation allele to your offspring. Your offspring that inherit the allele will either be premutation carriers, like yourself, or the allele will expand, and they will have a diagnosis of fragile X syndrome. Premutation allele carriers are at an increased risk for FMR1-related conditions.
We recommend that you share and discuss this information with all of your health care providers. Since this is an inherited gene change, this information may be helpful to share with family members as it may impact their family planning.
Fragile X syndrome is a condition associated with intellectual disabilities and cognitive impairment. Typically, males are more severely affected than females. Affected individuals have developmental delays, mild-to-moderate intellectual disabilities, and behavioral differences such as hyperactivity, anxiety, and autism spectrum disorders. Most males, and approximately half of affected females, have characteristic physical features including a long and narrow face, large ears, a prominent jaw and forehead, flat feet, and unusually flexible fingers.
Individuals who are carriers of a premutation allele are also at risk to develop FMR1-related conditions such as fragile X tremor ataxia syndrome (FXTAS) and/or primary ovarian insufficiency (POI).
Fragile X Tremor Ataxia Syndrome (FXTAS)
Both male and female premutation carriers (those with 55-200 CGG repeats) are at risk to develop a late onset (after age 50) neurological condition known as FXTAS. Individuals with FXTAS can develop trouble walking, leading to increased tendency to fall and subsequent use of walking aids. On average, male premutation carriers over age 50 have a 40% chance of developing FXTAS. The risk for female premutation carriers to develop FXTAS is not well-defined; however, females seem to be at a lower risk of developing FXTAS than males.
Fragile X-Associated Primary Ovarian Insufficiency (POI)
Females who are premutation carriers are at increased risk of POI (early menopause and reduced fertility). Approximately 1% of women in the general population develop POI, while premutation carriers have an up to 21% chance of developing POI. It is important to note that 5% to 10% of women with POI are able to conceive after receiving a diagnosis of POI.
Males who have Fragile X syndrome typically have developmental delays, intellectual disabilities, and may have autism spectrum disorders. Affected females may have a wider spectrum of features that vary in severity, but females are still at risk for significant intellectual involvement and autism spectrum disorders. Fragile X syndrome does not typically affect lifespan.
Treatment for fragile X syndrome is supportive as there is no cure. Early intervention, special education classes, and medication to treat behavioral issues may be indicated.
Talk to a Genetic Counselor
As a NxGen client, you'll have access to personal genetic counselors who can help explain the results of your screens and provide insight on how to move forward. To schedule a personal conference to discuss your screen results, call (855) 776-9436. or click the link below.Discuss Your Screening Results