Rs45477792

This SNP, also known as P532L, affecting an amino acid in exon 1 of the KCNA5 potassium channel gene, may mediate the response to drugs such as quinidine.

The risk allele is rs45477792(T), and carriers receiving quinidine or propafenone for the treatment of cardiac arrhythmias may be resistant to the drug (and thus treatment). Note that this allele is rare; it was not observed in Caucasian or Asian populations, however it is reported to be present at a frequency of 0.8% (i.e. less than 1%) among African-Americans.