Abstract: Objective To identify genes and mutations in three Chinese families who presented with X-linked retinitis pigmentosa. Design Gene research. Participants 3 Chinese XLRP families including 27 participants(18 male). Methods The clinical data and ophthalmic examinations of three families were collected by the same doctor. Genomic DNA was extracted from peripheral blood. The coding regions and intron-exon boundaries of the retinitis pigmentosa GTPase regulator (RPGR) and RP2 genes, including the open reading frame 15 (ORF15) of RPGR, were amplified by PCR and then sequenced directly. Main Outcome Measures Clinical characteristcs and gene sequencing. Results Mutation screening demonstrated two novel nonsense mutations (c.1541C>G;p.S514X and c.2833G>T;p.E945X) and one missense mutation(c.607G>C;p.A203P) in RPGR genes. Genotype-phenotype correlation analysis suggested that patients with mutation close to down-stream of ORF15 in family 3 manifested the early loss of cone function; female carries with ORF15 nonsense mutation showed heavier clinical manifestations. Thus, the inheritance patterns bias to dominant heredity. Conclusion We identified three novel mutations of RPGR genes, which broaden the spectrum of RPGR mutations and the phenotypic spectrum of the disease in Chinese family.

Key words: X-linked retinitis pigmentosa, DNA mutational analysis, pedigree, China