Objective To screen the mutations of MYOC gene in a Chinese primary open angle glaucoma (POAG) family from Cbengqing and investigate the relationship between the mutations in MYOC/TIGR gene and POAG.Methods In a large 4-generation glaucoma family, myocilin gene (MYOC) was screened in 39 family members, 8 of which were confirmed patients. Normal controls included 100 normal Chinese subjects.The known mutations of MYOC gene ( including G34C, C136T, G144T, G227A, C624G,G736A, C1009G, A1036G, C1081T, G1099A, G1138A, A1139C, T1430A, C1441A and C1442T) were detected by single strand conformation polymorphism(SSCP) , po]ymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) analysis and DNA sequencing.Results G227A mutation was detected in 2 POAG patients and 1 asymptomatic patient, but not in the controls.Cl009del mutation was identified in all patients of the pedigree and an offspring member but not in the controls. No other mutations were detected.Since the C1009del mutation was revealed for the first time, a new GenBank number FJ237047 correponding to ACI62293 was applied.Conclusions The G227A mutation is a known site and there is no relationship between G227A mutation and glaucoma. But C1009del may be related to glaucoma which suggests that morbidity could be higher in the relatives of POAG than the controls.