Rs17580

rs17580, also known as the S or PiS allele, is a SNP in the SERPINA1 gene.

Levels of alpha-1 antitrypsin (encoded by the SERPINA1 gene) may be reduced in carriers of the rs17580(T) allele, but there is no known association with liver disease or cystic fibrosis. The rs17580 PiS variant is most associated with risk of developing COPD, especially in smokers, but it's association with emphysema is variable. See rs28929474 for the most common pathologic SNP (PiZ) in the SERPINA1 gene.

Please be careful when interpreting results for this SNP as it is in dbSNP and SNPedia in minus orientation where the risk allele is T, but test results may be in the plus orientation where the risk allele is A (although currently 23andMe reports the risk allele as T). This SNP has an ambiguous flip which can make this very confusing.

a relatively small study of 182 patients found no association between rs17580 and risk for cholangiocarcinoma

Alpha-1 Antitrypsin Deficiency