rs121908555
A SNP in the SCN4A gene on chromosome 17. Its most notable genotype is A;G: possibility of Hypokalemic periodic paralysis
- Gene
- SCN4A
- Location
- Chr 1763,945,608 (GRCh38)
- Highest magnitude
- 3.0Important
- Tested on
- AncestryDNA
Genotypes
Plus strand, as in 23andMe and AncestryDNA files.
- G;GGoodcommon in clinvar
- A;GMost notableBadpossibility of Hypokalemic periodic paralysis
SNPedia records rs121908555 on the minus strand: (C;C), (C;T). Magnitude rates how notable a genotype is from 0 to 10, not how risky it is.
Related
Other SCN4A SNPs
- rs121908548C;TPotassium aggravated myotonia; paramyotonia congenitaVery important
- rs80338784C;Tpossibility of Hypokalemic periodic paralysisImportant
- rs80338785G;Tpossibility of Hypokalemic periodic paralysisImportant
- rs80338788C;Tpossibility of Hypokalemic periodic paralysisImportant
- rs751368967C;GSIDS predisposition??Worth knowing
- rs774452124C;TSIDS predisposition??Worth knowing
- rs774453167G;TSIDS predisposition??Worth knowing
Notes
From SNPedia
Notes
A;G
Hypokalemic periodic paralysis (hypoKPP) is an autosomal dominant skeletal muscle disorder, so carriers of one rs121908555(T) allele may be at risk for this disorder.
Source and license
Adapted from rs121908555 on SNPedia, using a snapshot taken October 16, 2026. SNPedia content is shared under CC BY-NC-SA 3.0 US, and this page is shared under the same license.
SNPedia is a community-edited wiki. Its entries can be incomplete, out of date or wrong, and nothing here is a diagnosis or medical advice. Magnitude is a community rating of how interesting a genotype is, not a risk score.