Rs1800709

rs41293463 is a SNP causing an amino acid change in the breast cancer 1 BRCA1 gene at amino position 841. The more common rs41293463(C) allele encodes Arg, while the rare rs41293463(T) allele encodes Trp; this SNP is also known as R841W.

A 1996 study of 305 cases in Southern California of breast cancer and ovarian cancer found 3 cases carrying the rs1800709(T) allele. In all three cases, there was a strong family history of breast, ovarian, or other cancers, and family members showed a high concordance of cancer incidence with the presence of this SNP. However, the age of cancer onset was the same as for sporadic cases. The authors conclude that this SNP may explain around 1% (CI: 0-1.7%) of all breast and ovarian cancers, at least for this population.

Note: this SNP is rather unlikely to be a causative or high penetrance mutation, given it's frequency in the population at large.


 * See also Omim 113705.0022