Table 2.

Allelic Disorders

GeneDisorderMOIAssociated Pathogenic Variant(s) / Comments
MY07A DFNA11 1ADA unique putative dominant-negative variant in the coiled-coil domain necessary for myosin VIIa homodimer formation 2
DFNB2 1ARNote: A reanalysis of the phenotype in 1 large DFNB2 pedigree revealed presence of RP, indicating that the affected persons have USH1B (not DFNB2) & reinforcing the need for a multidisciplinary approach in making an accurate diagnosis of USH. 3
USH1C Homozygous 11p15-p14 deletion syndrome (OMIM 606528)ARA contiguous gene deletion incl USH1C causes infantile hyperinsulinism, enteropathy, & deafness.
DFNB18 1ARLess deleterious variants in USH1C may be assoc w/deafness w/o RP. 4
Nonsyndromic hearing lossADSensorineural hearing impairment w/o RP 5
USH3ARRP w/late-onset high-frequency hearing loss 6
USH2, atypical USHARA wide range of auditory & retinal phenotypes have been found in persons w/biallelic CDH23 pathogenic variants, some more consistent w/USH2 than w/USH1. 7
PCHD15 DFNB23 1ARMissense variants have been found to cause DFNB23, 8 while more severe variants (splicing, frameshift, nonsense, large deletions) cause USH1.
USH1G USH2, atypical USHARSome pathogenic variants in USH1G have been shown to cause a relatively mild form of USH, more consistent w/USH2 than w/USH1. 9

AD = autosomal dominant; AR = autosomal recessive; DFNA = nonsyndromic deafness, autosomal dominant; DFNB = nonsyndromic deafness, autosomal recessive; MOI = mode of inheritance; RP = retinitis pigmentosa; USH = Usher syndrome; USH1 = Usher syndrome type I; USH2 = Usher syndrome type II


From: Usher Syndrome Type I

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