The more X chromosomes they have, the more severe their symptoms will be.
Symptoms of more severe Klinefelter types include: Klinefelter syndrome is one of the most common chromosome conditions in newborns.
The condition is most commonly diagnosed as a result of fertility investigations as KS adults are almost always unable to father children by normal means. The usual treatment is testosterone replacement therapy although this may not suit all.
Sometimes symptoms are so mild that they go unnoticed.
Or symptoms can be misdiagnosed being caused by other similar conditions.
Starting treatment early can prevent some of the symptoms.
One of the main treatments is testosterone replacement therapy.
It is a common congenital condition which is found in around 1 in 600 live male births and is caused by the presence of one or more additional sex chromosomes. KS is diagnosed by a genetic blood test which identifies the karyotype – 47, XXY.