What Is Triple X Syndrome?

What Is Triple X Syndrome?

Triple X syndrome, otherwise referred to as Trisomy X or 47,XXX, is a genetic disorder where girls are born with three X chromosomes rather than two. It most often occurs randomly and isn't inherited from parents. Most girls with this disorder don't have any obvious signs and can live their lives without realising they have it. In others, it can lead to learning delay, speech problems, social impairment, or emotional change. Diagnosis is through a chromosome test following observation of developmental problems. Read on to know more.

Triple X syndrome, otherwise referred to as Trisomy X or 47,XXX, is a genetic disorder where girls are born with three X chromosomes rather than two. It most often occurs randomly and isn't inherited from parents. Most girls with this disorder don't have any obvious signs and can live their lives without realising they have it. In others, it can lead to learning delay, speech problems, social impairment, or emotional change. Diagnosis is through a chromosome test following observation of developmental problems. Read on to know more.

Causes

Triple X syndrome is caused by a random genetic error during cell division. This error can occur either before conception, during the formation of the egg or sperm, or shortly after fertilisation, in the early stages of embryonic development. Depending on when the error occurs, triple X syndrome can appear in different forms:

• Nondisjunction during egg or sperm formation:

It happens due to the failure of chromosomes to separate properly during cell division. If an egg or sperm contains two X chromosomes instead of one and it combines with another X chromosome from the other parent, the result is a female with three X chromosomes (47,XXX).

• Mosaicism:

In some cases, the extra X chromosome appears after fertilisation, during early cell divisions in the developing embryo. This results in mosaic triple X syndrome, where some cells have two X chromosomes (46,XX) and others have three (47,XXX).

In rare instances, the risk of having a child with triple X syndrome may slightly increase if the mother is 35 years or older at the time of conception. Hence, you should consult your doctor during your pregnancy about possible genetic conditions. The testing for which should be covered under health insurance.