What is triple X syndrome?
Triple X syndrome, also known as XXX syndrome, triplo-X and trisomy X, is a disease characteristically occurring in females, who instead of normal two X chromosomes carries one extra X chromosome. This condition is not very uncommon affecting about 1 in every 1000 females. Triple X syndrome usually does not lead to any symptoms, however, if present symptoms include excessive height, presence of fold of skin on the inner aspect of the eyes, weak muscle activities, poor mental and behavioral state. This disease is not hereditary rather developmental defect in the ovum or sperm may lead to one extra chromosome in the patient’s body. There is no cure for triple X syndrome, however counseling of the patients and the parents along with educational support help the affected person to lead to normal life.
Signs and Symptoms
In majority of the patients suffering from this condition there may not be any symptom other than tall stature however if present these children suffer from developmental delay in learning, speech or other motor activities. One characteristic learning disability is dyslexia, a type of reading disability.
Other physical symptoms include presence of extra skin fold covering the inner part of the eyes (epicanthal folds), weak, flaccid muscle due to poor muscle tone, small size of head in contrast to whole body size, sideways bending of the back bone (scoliosis), constipation and pain in the abdomen. In some women of triple X syndrome there is premature failure of the ovary however in most of the patients fertility remains normal.
Females suffering from triple X syndrome usually show poor academic results, low-self confidence, suffer from anxiety and become excessively shy.
Causes and Risk Factors
There are 23 pairs of chromosome in human body of which 22 pairs are autosome and one pair is sex chromosome which determines the gender of the person. Females have sex chromosome as XX whereas males have sex chromosome as XY. Every child inherits one sex chromosome from mother and one from father. Mother can give the child only X chromosome whereas father can give either X or Y.
Triple X syndrome affects females and there is one extra copy of X chromosome besides the usual two copies of the X chromosome. Although this condition occurs due to chromosomal abnormality however this condition is not inherited rather the X chromosome is formed if there is any abnormality during development of the egg cell (ovum) of the mother or the sperm of the father.
In these patients this error occurs during cell division process of the ovum or the sperm and known as nondisjunction. In other patients this extra X chromosome may be present only in few cells of the body leading to a mosaic form of the disease. Mosaic form of triple X syndrome have less severe symptom in comparison to frank triple X syndrome. Conception at elderly age both for mother and father may be a risk factor.
Treatment of Triple X Syndrome
As it is a chromosomal abnormality there is no permanent cure for this disease however counseling of the patient and parents along with educational support usually helps in leading normal life.