OBJECTIVETo detect gene mutations associated with autosomal dominant congenital stationary night blindness(ADCSNB) in a large Chinese family.

METHODSGenomic DNAs were extracted from peripheral blood samples of 16 affected and 14 unaffected family members. According to 5 missense mutations in 3 genes reported previously, 4 pairs of primers were designed and corresponding exons containing the five mutation sites were amplified by polymerase chain reaction. Amplified products were purified and sequenced by MegaBACE1000 capillary array electrophoresis DNA sequencer. Full field electroretinogram (ERG, ISCEV) of patients was recorded and analyzed by Roland Consult System.

RESULTSDark-adapted ERG showed a-wave was normal, but b-wave of the patients was markedly decreased. None of the five missense mutations were detected in 16 affected and 14 unaffected family members.

CONCLUSIONThe molecular pathogenesis of ADCSNB in this family does not involve point mutations or deletions of these five sites, which indicates the heterogeneity of ADCSNB.