Description
Variant summary: CACNA1C c.5731G>C (p.Gly1911Arg) results in a non-conservative amino acid change located in the Voltage-gated calcium channel subunit alpha, C-terminal domain of the encoded protein sequence. Three of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 6e-05 in 249708 control chromosomes, predominantly at a frequency of 0.00056 within the East Asian subpopulation in the gnomAD database. The observed variant frequency within East Asian control individuals in the gnomAD database is approximately 56 fold of the estimated maximal expected allele frequency for a pathogenic variant in CACNA1C causing Arrhythmia phenotype (1e-05), strongly suggesting that the variant is a benign polymorphism found primarily in populations of East Asian origin. The variant, c.5731G>C, has been reported in the literature in individuals affected with Brugada Syndrome, long QT syndrome or sudden unexplained infant death (Allegue_2015, Hennessey_2014). However, one publication, Hennessey_2014, suggests the variant is inherited from the asymptomatic father, although his DNA was not available for analysis. In electrophysiological analyses, the variant was observed to cause a gain of function of CaV1.2 suggesting increased susceptibility for arrhythmias in certain clinical settings (Hennessey_2014). Four ClinVar submissions from clinical diagnostic laboratories (evaluation after 2014) cites the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as VUS - possibly benign.
| # | Sample | Method | Observation |
|---|
| Origin | Affected | Number tested | Tissue | Purpose | Method | Individuals | Allele frequency | Families | Co-occurrences |
|---|
| 1 | germline | unknown | not provided | not provided | not provided | | not provided | not provided | not provided | not provided |
