OBJECTIVETo obtain allelic loss mapping and define the minimal lost region on chromosome 1q21 in gastric carcinomas, and explore role of 1q21 loss of heterozygosity (LOH) in the development and progression of gastric carcinogenesis.

METHODSUsing 7 high-density microsatellite markers and PCR method, lq21 LOH was analyzed in 30 paired specimens of fresh gastric carcinoma, and the relation between 1q21 LOH and the clinicopathological features of the malignancy was tested.

RESULTSThe LOH frequency on chromosome 1q21 from these gastric carcinoma tissues reached 60% (18/30). The LOH frequencies of the microsatellite markers D1S514, D1S2696, D1S498, D1S305, D1S2624, D1S2635 and D1S2702 were 13.3%, 10%, 20%, 23.3%, 33.3%, 40% and 23.3%, respectively. The minimal lost region on 1q21 LOH in the gastric carcinoma tissues was located in the region between D1S2624 and D1S2707, in the vicinity of D1S2635. No significant relations of 1q21 LOH to the patients' age, gender, location of the primary foci, clinical staging, or the tumor differentiation were noted (P>0.05), but 1q21 LOH was correlated to lymph node metastases of the malignancy (P<0.05).

CONCLUSIONHigher frequency of 1q21 LOH occurs in gastric carcinoma cells, suggesting the presence of potential tumor suppressor genes closely associated with gastric carcinogenesis near the region of D1S2635.