Sex - Basic Aspects of Human Sexuality

The Role of Chromosomes - Problematic Developments: Table 1.2

Chromosomal Problems Modern research has found a number of possible atypical chromosomal conditions. The following desribes only the most important of them. As a rule, they concern deviations from the regular XX- or XY-combination. They are found in ca. 0,5 to 1 percent of the population.

In Boys 1. The so-called Klinefelter Syndrome, i.e. the chromosomal combination XXY (or, very rarely, XXXY). It manifests itself in underdeveloped testicles, a low level of testosterone, a growth of breasts, disproportionate arms and legs, infertility and a likelihood of language disability. Hormonal treatments in adolescence can often achieve a masculinization of the body. The syndrome is found in one of ca. 1000 live births. 2. The XYY Syndrome manifests itself in malformations of the sex organs, reduced fertility, and other possible problems. The syndrome is found once in ca. 1000 live births.