Q92: Other trisomies and partial trisomies of the autosomes, not elsewhere classified

Q92.6: Extra marker chromosomes

Somatic cells usually hold a complete blueprint of your body. This blueprint consists of genetic information. The genetic information is encrypted in the chromosomes. In humans, somatic cells usually have 23 pairs of chromosome, so 46 chromosomes in all.

An additional small chromosome is also called a marker chromosome. With the additional marker chromosome you have more chromosomes than usual. A marker chromosome can appear in all body cells or only in part of the cells. A child can inherit a marker chromosome from a parent. However, marker chromosomes can also be created again.

The effects of extra marker chromosomes are very different. The effects depend, among other things, on which parts of the genetic information the marker chromosome contains.