Turner's syndrome diagnosis

By Dr Joe Kabyemela, MD

Turner’s syndrome is a condition that is caused by absence of one sex chromosome. A normal human being has 23 pairs of chromosomes, making a total of forty-six chromosomes. One of the pairs is made up of sex chromosomes.

The female sex chromosomes are XX and the male chromosomes are XY. A woman is therefore represented as 46XX and a man as 46XY.

A Turner's syndrome person is represented as 45X0 (the 0 standing for a missing chromosome). Turner's syndrome is also called Monosomy X

Gender of a Turner's syndrome individual

A Turner’s syndrome baby will be female. There is a normal vagina, a uterus and tubes. The ovaries are, however, streaky and non-functional. This means a Turner's girl cannot ovulate. Nor can she conceive in the normal way.

Long term prospects for a Turner's syndrome baby

Leaving fertility issues aside; in the short and long term, the overall prospects of a Turner’s syndrome baby are pretty good. In fact, in a good number of Turner's syndrome girls, the diagnosis is not made until their early or mid-teens.

However, there are some physical characteristics which may arouse suspicion of something amiss. These may include short stature and a webbed neck.

There may also be heart or kidney anomalies, which may lead to investigations for chromosomal defects. Intellectually, they tend to be of average intelligence but they can also excel.

Prenatal diagnosis of Turner’s syndrome

There are no biochemical or specific ultrasound diagnostic features for Turner's syndrome. There is, however, a lethal form of Turner's, where quite marked physical and heart abnormalities may be detected on ultrasound. Such pregnancies tend to end in miscarriage or stillbirth. This lethal form affects only a minority of Turner's syndrome babies.

Maternal age and risk of Turner's syndrome

The overall risk is estimated at one in 2500 and is constant at any maternal age. Paternal age, likewise, has no influence on the risk rate.

Next Page: Klinefelter’s Syndrome

Child with some of the classic features found in Turner’s syndrome: A wide webbed neck, nipples wide apart, exaggerated carrying angle and short stature. Many Turner’s syndrome girls will not have many of these features