Purpose  Consanguineous marriages are common phenomenon in remote areas of Ningxia, an autonomous region in northwest China. In the present study, the influence of consanguinity on the prevalence of retinitis pigmentosa was examined.
Methods  A total of 121 retinitis pigmentosa patients who attended Ningxia People’s Hospital during the period April 2009 to April 2011 were recruited. Information of family history and marriage was documented. They all received complete ophthalmoscopic examination. All patients were natives of Ningxia.
Results  Twenty (16.5%) of the patients from thirteen families reported a family history of consanguinity. Eleven of these families were from south Ningxia and only two from north Ningxia. The most common form of consanguineous union was between first cousins (n = 19), followed by uncle/aunt marriage. Three families with deafness were diagnosed as Usher syndrome. Members of one family had glaucoma, cataract and macular edema. The other sixteen families were diagnosed as primary RP. The common features of these patients are early age of onset, rapid disease progression and severe visual impairment.
Conclusions  Consanguineous marriage is closely related with retinitis pigmentosa in Ningxia. Genetic analysis, started with RP1 sequence studies, of these families are in progress.