MYO7A p.Glu968Asp

The c.2904G>T variant in MYO7A is a missense variant predicted to cause substitution of glutamic acid by aspartic acid at amino acid 968. The highest population minor allele frequency in gnomAD v2.1.1 is 0.0000064 (3/126898 alleles) in the European (non-Finnish) population, which is lower than the ClinGen Hearing Loss VCEP threshold (<0.00007) for PM2_Supporting, meeting this criterion (PM2_Supporting). The computational predictor REVEL gives a score of 0.563, which is neither above nor below the thresholds predicting a damaging or benign impact on MYO7A function. At least one patient with this variant displayed Usher syndrome (PP4, PMID: 33089500). This variant has been detected in at least five individuals with Usher syndrome. Of those individuals, two were compound heterozygous for the variant and a pathogenic or likely pathogenic variant and presumed to be in trans (c.631A>G (p.S211G) and c.3719G>A (p.D1240Q)) and three of those were confirmed in trans by family testing and all of whom had different variants on the other allele (c.224dup (p.D75fs), c.487G>C (p.G163R), c.1189G>A (p.A397T); 2.5 PM3 points, PMID: 25472526, 26969326, 33089500; ClinVar Variation ID: 43325, 43218, 553215) (PM3_Strong). The variant has been reported to segregate with Usher syndrome in three affected family members from one family (PP1; PMID:33089500). Another missense variant, c.2904G>C (p.E968D), in the same codon has been reported in a patient with Usher syndrome (PMID:27460420). However, this variant has not yet met the criteria to be classified as pathogenic or likely pathogenic by the ClinGen Hearing Loss VCEP (PM5 not met). In summary, this variant meets the criteria to be classified as likely pathogenic for autosomal recessive Usher syndrome based on the ACMG/AMP criteria applied, as specified by the ClinGen Hearing Loss VCEP: PM2_P, PP1, PP4, PM3_S (ClinGen Hearing Loss VCEP specifications version 2; 7/26/2022).