Marker HumARA

We announce here that our group no longer considers HumARA a suitable DNA marker in forensic casework.

Desmarais et al. [1] have used HumARA typing as a starting point to generate specialized formulae for ChrX typing in forensic practice. Hence, these markers are well established in forensic DNA typing. However, it has been known from the very beginning of HumARA testing that the HumARA CAG repeat, in contrast to all other forensic DNA markers, is located in a coding region (androgen receptor gene, exon 1). This means the repeat codes for a polyglutamine tract. La Spada et al. [2] proved that X-linked spinal and bulbar muscular atrophy (SBMA) is attributable to a mutation at this locus; the disease occurs when there are trinucleotide repeat lengths of more than 43 bp.

Apart from the SBMA disease, HumARA typing can detect a number of further health risks, such as an increased risk of impaired spermatogenesis and increased risks of breast, endometrial, colorectal, and prostate cancer.

1. Desmarais D, Zhong Y, Chakraborty R, Perreault C, Busque L (1998) Development of a highly polymorphic STR marker for identity testing purposes at the human androgen receptor gene (HUMARA). J Forensic Sci 43: 1046-1049.
2. La Spada AR, Wilson EM, Lubahn DB, Harding AE, Fischbeck KH (1991) Androgen receptor gene mutations in X-linked spinal and bulbar muscular atrophy. Nature 352: 77-79.