ClinVar

Description

Variant summary: ACADVL c.1066A>G (p.Ile356Val) results in a conservative amino acid change located in the Acyl-CoA dehydrogenase/oxidase C-terminal domain (IPR009075) 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 0.00085 in 250672 control chromosomes, predominantly at a frequency of 0.011 within the African or African-American subpopulation in the gnomAD database, including 2 homozygotes. The observed variant frequency within African or African-American control individuals in the gnomAD database is approximately 4-fold of the estimated maximal expected allele frequency for a pathogenic variant in ACADVL causing Very Long Chain Acyl-CoA Dehydrogenase Deficiency phenotype (0.0029), strongly suggesting that the variant is a benign polymorphism found primarily in populations of African or African-American origin. c.1066A>G has been reported in the literature in individuals with abnormal newborn screening results, hypoglycemia or fatty acid oxidation defects (Ndukwe_2013, Miller_2015, Pena_2016, Hesse_2018, Tangeraas_2020). These reports do not provide unequivocal conclusions about association of the variant with Very Long Chain Acyl-CoA Dehydrogenase Deficiency. At least one publication reports experimental evidence evaluating an impact on protein function. The most pronounced variant effect results in 30%-50% of normal activity (Hesse_2018). Three ClinVar submitters (evaluation after 2014) cite the variant as benign and four ClinVar submitters (evaluation after 2014) cite it as uncertain significance. Based on the evidence outlined above, the variant was classified as likely benign.