A novel USH2A gene mutation in a family with retinitis pigmentosa: A case report
We report a novel variant of the USH2A gene in a family affected by retinitis pigmentosa (RP). Genomic DNA was obtained from a 55-year-old woman (the proband) with night blindness who was diagnosed with non-syndromic RP. We identified the compound heterozygous variants c.8559-2A>G and c.151A>T (p.Ile51Phe) in the USH2A gene as the underlying cause in the proband; the former variant, instead of the latter variant, has been reported in the literature. The proband’s mother carried the c.151A>T variant, while her father and daughter carried the c.8559-2A>G variant. In this family, the proband and her mother developed RP; however, her father and daughter did not develop the disease. Although in silico tools predicted that c.151A>T is benign, segregation analysis suggested that this variant could be potentially harmful. The identification of c.151A>T (p.Ile51Phe) variant is a novel finding, and this variant might be a potentially harmful variant of USH2A gene. This finding also further expands the mutation spectrum of this gene in the Chinese population.
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