Reported by ClinVar to cause familial episodic pain syndrome (https://www.ncbi.nlm.nih.gov/clinvar/variation/157599/). In ClinVar this variant is reported as “pathogenic” (causing this condition) by a single source, OMIM, which cites Huang et al 2014 (https://www.ncbi.nlm.nih.gov/pubmed/24776970). However, it is reported as “uncertain significance” by Emory Genetics Laboratory.
Huang et al found this variant heterozygous in two of 345 patients screened with painful peripheral neuropathy. The authors also report molecular evidence that this variant disrupts the function of the SCN11A protein product. This variant is uncommon but not rare: according to ExAC it is carried by 1 in 600 Europeans (http://exac.broadinstitute.org/variant/5-176048219-G-T).
The frequency of this variant seems at odds with a proposed “rare disease” effect, and the statistical significance of Huang et al’s observation may be weak or absent. They report the variant is also seen in EVS, and a two-tailed Exact Fisher test using their reported numbers produces a p-value of 0.087.