An autosome is a non-sex chromosome. It is an ordinarily paired^[1] type of chromosome that is the same in both sexes of a species. For example, in humans, there are 22 pairs of autosomes. The X and Y chromosomes are not autosomal. Non-autosomal chromosomes are usually referred to as sex chromosomes, allosomes or heterosomes.

Like other chromosomes, autosomes display STR and SNP mutations which can be observed and have been used in genetic testings for ancestry, ethnicity, race and genealogical purposes. Private testing companies which do autosomal STR tests include FamilyTreeDNA and DNAtribes. Whereas companies testing autosomal SNPs include AncestryByDNA and deCODEme.

Notes

1. ^ In the case of higher ploidy levels than the usual diploid, there will be the same number of an autosome as the ploidy level itself. For example, in a pentaploid, there will be five copies of each autosome.

See also

• Autosomal dominant
• Autosomal recessive
• CODIS
• Homologous chromosome
• OmniPop
• Allosome

External links

• Discussion thread on the potential use of autosomal 'Haploblocks' in advanced methods of genetic genealogical testing
• ENFSI autosomal DNA database allele population frequency calculator
• CSFS autosomal DNA database allele population frequency calculator
• MSNBC article on autosome testing companies including 23andme, deCODEme & Navigenics