||Common in Caucasians; GSTM1*0/0 null status
Although located 11kb away from it, rs366631 is effectively a pseudo-SNP tagging the status of the GSTM1 gene, due to the nature of the duplications and deletions in this part of chromosome 1.[PMID 18948376]
In typical microarray-based genotyping results, the correspondence between the rs366631 call and GSTM1 allele status is the following:
- rs366631(T;T): GSTM1*0/0, i.e. GSTM null allele (double deletion)
- rs366631 (C;T) and (C;C): GSTM1*1, i.e. at least one functional GSTM1 gene copy is present
The GSTM1*0/0 null phenotype has a frequency of greater than 50% among Caucasian, Chinese, and Indian populations, and sporadic reports over the years (many based on rather small sample sizes) indicate that it may be a slight risk factor for certain cancers based on increased sensitivity to particular chemical carcinogens.
|Desc||GLUTATHIONE S-TRANSFERASE, MU-1; GSTM1|
[PMID 18496134] Identification of genetic variants and gene expression relationships associated with pharmacogenes in humans.
[PMID 18948376] Population-specific GSTM1 copy number variation.