What is Klinefelter syndrome?
The Klinefelter syndrome occurs in about every 750th man. It is one of the most common congenital chromosomal diseases in which affected men have one sex chromosome too many. They usually have the karyotype 47XXY instead of the usual 46XY. The double X in the chromosome set leads to a testosterone deficiency, which continues to cause typical symptoms of Klinefelter’s syndrome. Learn more about this.
What causes Klinefelter syndrome?
Klinefelter’s syndrome is not a disease that is passed on from parents to their children. It is more likely to occur accidentally due to a disorder during meiosis. During this meiosis, sperm and eggs are produced.
It is important in meiosis that one chromosome each is distributed to the male and female sperm cells. This is not the case with Klinefelter’s syndrome. Either the sperm or the egg have an additional X chromosome.
This means that one sex chromosome is too many when fertilized. This is also called chromosome aberration. The clinical picture only manifests itself in men, who usually have the karyotype 47XXY instead of 46XY.
The additional X chromosomes cause a testosterone deficiency, which has further consequences. A disease, which is also based on an altered number of chromosomes, is the Turner syndrome. The Klinefelter syndrome is a congenital chromosomal disease.
The cause of the disease is a disorder during the maturation of sperm and egg cells – also called meiosis. The chromosomes are not distributed exactly equally, so that one sperm or egg cell contains an additional X chromosome. Klinefelter’s syndrome is not a disease passed on from parents to children. It develops by chance. It is therefore neither inheritable nor contagious.
These symptoms may indicate Klinefelter syndrome
The typical symptoms that occur in Klinefelter’s syndrome are caused by a testosterone deficiency. It usually results in the following appearance: small testicles: In infancy, an undescended testicle is often first seen, which can be unilateral or bilateral. Adults with Klinefelter syndrome usually have a small testicle.
Small penis: In addition, affected persons usually have a small penis. A lack of sperm can also lead to infertility.
- Small testicle: Often an undescended testicle occurs first in infancy, which can be unilateral or bilateral.
Adults with Klinefelter syndrome usually have a small testicle.
- Small penis: In addition, affected persons usually have a small penis. A lack of sperm can also lead to infertility.
Altered muscle and fat mass: Testosterone supports muscle growth. In Klinefelter’s syndrome, low testosterone levels result in reduced muscle mass in favor of fat mass.
Those affected have an increased fat deposit and tend to be overweight. High growth: Due to the lack of testosterone, the growth joints close later, resulting in increased length growth. Affected persons are above average in size.
- Altered muscle and fat mass: Testosterone supports muscle growth. In Klinefelter’s syndrome, low testosterone levels result in reduced muscle mass in favor of fat mass. Those affected have an increased fat deposit and tend to be overweight.
- High growth: Due to the lack of testosterone, the growth joints close later, resulting in increased length growth.
Those affected are above average in size.
- These are the symptoms of ADHS
- Problems at school
Affected persons often have an undescended testicle, a small limb and muscle weakness already in infancy. Speech development is usually delayed. Learning and reading difficulties can occur in school children.
In adolescence there is usually a delayed onset of puberty, breast growth and strong growth in length. Adults may also have erection problems and impotence. If left untreated, it can also lead to the development of overweight with the development of diabetes mellitus 2 and vascular diseases. The diagnosis of Klinefelter’s syndrome can be made in the womb by examining the amniotic fluid or taking a sample from the placenta.Subsequently, the diagnosis can be made by means of a blood sample, in which the chromosome set is examined. However, this requires a human genetic expertise.
