{{Rsnum 
|rsid = 45438698
|Gene =  KCNA5
|geno1 = (A;A)
|geno2 = (A;G)
|geno3 = (G;G)
|ReferenceAllele=G
|MissenseAllele=A
|Orientation=plus
|Chromosome=12
|position=5045880
|Assembly=GRCh38
|GenomeBuild=38.1
|dbSNPBuild=141
|Status=Merged
|Merged=12720445
|Gene_s=KCNA5
}}This SNP, also known as R578K, affecting an amino acid in exon 1 of the [[KCNA5]] potassium channel gene, may mediate the response to drugs such as [[quinidine]] and [[propafenone]].

The risk allele is [[rs45438698(A)]], 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 African-American or Asian populations, however it is reported to be present at a frequency of 1.1% among Caucasians.
{{PMID|15735608}}
{{ neighbor
| rsid = 45477792
| distance = 138
}}

{{on chip | FTDNA2}}
{{on chip | HumanOmni1Quad}}