Pregnancy & The Fragile X Syndrome Test

One of the big concerns for many couples who are preparing for a pregnancy is the possibility that their child will inherit a familial disease. One such illness is Fragile X Syndrome, a disease that can be potentially passed down from parent to child.

What is Fragile X Syndrome?

Genes are responsible for virtually everything in the human body. They are a set of instructions which tell our systems what to do and how to do it. So naturally when something goes wrong with particular genes the results are disease. Genetic diseases can usually be passed down from parent to child as we inherit our genetic material from our parents, a copy from our mother, and a copy from our father.


Genes are arranged on structures called chromosomes, and the chromosomes which determine our gender are called the X and Y-chromosomes. Women have two copies of the X gene, while men only have the one as well as a copy of the Y chromosome. Fragile X Syndrome is a disease that affects the X chromosome, and is one of the leading genetic causes of mental impairment.

Fragile X Syndrome can cause anything from smaller scale learning difficulties to severe mental retardation. People suffering from Fragile X Syndrome also present some behavioural difficulties which are comparable to autism, including trouble with social interaction and repetitive, obsessive behaviour. The disease also presents with some characteristic physical features, and female carriers of the gene can experience fertility issues.

Testing for Fragile X Syndrome

As a condition with lifelong consequences for a child and his or her family, Fragile X Syndrome can be a concern for anyone with a family history of the disease. Fragile X can be inherited from a carrier with no outwards symptoms. Because the disease causing mutation on Fragile X is present on the X chromosome men, who only have one copy of this chromosome, can’t be carriers, as they will be affected by the disease. Women however, who have two copies of the X chromosome, can possess one faulty X chromosome which is compensated for by the other healthy X chromosome. As such, only mothers to be need be tested for the disease.

The test for Fragile X Syndrome is called the Fragile X Syndrome Genetic Screening Test, or the FXS Genetic Test. This test is unique to the syndrome as it is slightly more technically complicated to test for when compared to other genetic illnesses.

The FXS Genetic Screening Test is available in the UK from private sources and the NHS. If you are interested in pursuing a genetic screen then the first port of call is your GP, who will be able to refer you to your closest NHS genetics service. Alternatively if you are looking for a private test then all you would have to do is contact the test provider with your concerns. The most relevant information you need to be able to provide to any test provider will be your family history of the disease.


« Pregnancy & The Bloom Syndrome Test Pregnancy & The Fanconi Anaemia Test »




PREGNANCY