The c.664G>A (NM_000018.4) variant in ACADVL is a missense variant predicted to cause substitution of glycine by arginine at amino acid 222 (p.Gly222Arg). This variant has been detected in at least four individuals with very long chain acyl CoA dehydrogenase (VLCAD) deficiency. This variant has been detected in at least four individuals with very long chain acyl CoA dehydrogenase (VLCAD) deficiency. Of those individuals, two were compound heterozygous for the variant and a distinct variants not yet evaluated by the ACADVL VCEP, at least one individual was compound het for this variant and a variant determined by the ACADVL VCEP as likely pathogenic, and at least one individual was homozygous for the variant (PM3_Supporting, PMID: 24801231, 20060901, 16443431, 28771436, 31844625). At least one patient with this variant displayed increased C14:1 levels and another patient showed significantly reduced very long chain acyl-CoA dehydrogenase (VLCAD) enzyme levels, which is highly specific for VLCAD deficiency (PP4_moderate, PMID: 24801231, PMID: 20060901). The highest population minor allele frequency in gnomAD v2.1.1 is 0.00003 in the South Asian population, which is lower than the ClinGen ACADVL Variant Curation Expert Panel threshold (<0.001) for PM2_Supporting, meeting this criterion (PM2_Supporting). The computational predictor REVEL gives a score of 0.981, which is above the threshold of 0.75, evidence that correlates with impact to ACADVL function (PP3). This variant resides within a region, amino acids 214-223, of ACADVL that is defined as a critical functional domain by the ClinGen ACADVL Variant Curation Expert Panel (PMID: 9973285, 18227065, 20060901; PM1). In summary, this variant meets the criteria to be classified as likely pathogenic for autosomal recessive VLCAD deficiency based on the ACMG/AMP criteria applied, as specified by the ClinGen ACADVL Variant Curation Expert Panel: PM1, PM2_supporting, PM3_Supporting, PP3, PP4_moderate