Association between three polymorphisms in RP1 hotspot region and risk of retinitis pigmentosa in Italian patients: A pilot study

Retinitis pigmentosa (RP) represents a heterogeneous inherited ocular disorder characterized by progressive retinal degeneration. Individuals affected by RP show night blindness, tunnel vision and progressive visual field reduction which usually culminates in complete blindness. Histologically, accumulation of lipofuscin granules represents the most frequent sign. Today, more than 80 genes are associated with RP, and among them RP1 is one of the most frequently mutated. Variants in this gene may be inherited as autosomal recessive, dominant, X-linked or sporadic patterns. In Italian individuals affected by RP we detected three polymorphisms within RP1 exon 4 (rs446227, rs414352, rs441800), falling in its exon 4 hotspot polymorphic region, and without a certain association with RP disease. Therefore, we studied the frequencies of the previously cited polymorphisms in the Sardinian population and verified a possible association with RP. The analyses showed a significant association, although we cannot exclude the role of the three polymorphisms in other related disorders.