Abstract
Purpose: :
PRPF31 is a core component of the U4/U6/U5 tri-snRNP complex which constitutes the pre-mRNA processing spliceosome. Over 50 different mutations have been reported in PRPF31 to cause autosomal dominant retinitis pigmentosa (ADRP), a clinically and genetically heterogeneous group of inherited retinal degenerations. A range of phenotypic characteristics as well as incomplete penetrance is common in families carrying PRPF31 mutations. We report a novel mutation in this gene in multiple members of a Caucasian USA family.
Methods: :
Direct genomic sequencing of the entire PRPF31 coding region and flanking intronic sequences was performed. Clinical findings in the proband and her siblings were reviewed.
Results: :
The proband presented at the age of 41 years with a diagnosis of ADRP. Her nyctalopia started in her 20s and peripheral vision loss in the 30s. An ERG was performed at the age of 24 and showed severely reduced scotopic and photopic responses. At her latest visit, visual acuity (VA) was 20/25 OU with a myopic correction. Her color vision was normal. There were peripheral ring scotomas in both eyes. Ophthalmoscopy showed changes typical of RP and myopia. Genetic testing at a CLIA certified laboratory revealed a novel PRPF31 mutation, c.915_916insTGT (p.Val305_Asp306insCys). We confirmed the mutation in our laboratory and tested her two sisters ages 51 (VA 20/60 OD and 20/70 OS) and 52 (VA 20/200 OD and 20/400 OS); both sisters had typical RP and the older one had developed anterior and posterior uveitis, macular edema and cataracts. Both carried the identical mutation. Their father reportedly was totally blind from RP.
Conclusions: :
We report a novel mutation in exon 9 of PRPF31 in a family with ADRP. The phenotype appears to consist of signs and symptoms that appear in the twenties and relentlessly progress with peripheral and central vision in the 50s. The association with uveitis in one family member is unclear.
Keywords: genetics • mutations • retinal degenerations: hereditary