ClinVar

Description

Variant summary: CYP21A2 c.1385T>C (p.Leu462Pro) results in a non-conservative amino acid change in the encoded protein sequence. Four of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 1.4e-05 in 142500 control chromosomes (gnomAD). c.1385T>C has been reported in the literature as a compound heterozygous genotype in trans with a pathogenic variant in an individual affected with non-classical Congenital Adrenal Hyperplasia (Karlsson_2019). However, this individual also had a variant in cis which, when expressed together with the variant of interest as a complex variant in vitro, showed a greater reduction of enzyme activity than when either variant was examined in isolation (Karlsson_2019). This report does not provide unequivocal conclusions about association of the variant with Congenital Adrenal Hyperplasia. Experimental evidence evaluating an impact of p.Leu462Pro on protein function found that the variant results in 55% and 40% of WT enzymatic activity towards 17OHP and progesterone, respectively (Karlsson_2019). The following publication has been ascertained in the context of this evaluation (PMID: 31344365). No submitters have cited clinical-significance assessments for this variant to ClinVar after 2014. Based on the evidence outlined above, the variant was classified as VUS-possibly pathogenic.