To determine the minimal region of deletion on 21q22 in gastric cancer, we
performed a high-density loss of heterozygosity (LOH) study with eight poly
morphic microsatellite markers. Among the 43 tumors examined, 20 (50%) of 4
0 informative carcinomas showed LOH at one or more loci. The peak LOH frequ
ency was identified at D21S1820 (34.2%) in 21q22.3. This data suggests that
this locus might harbor a new tumor suppressor gene in an area <0.332 Mb i
n physical map distance defined by D21S1820 and D21S49. Thus, we speculate
that trefoil factor family 1 (TFF1), located in this narrow region, might b
e the most probable candidate gene involved in gastric cancer carcinogenesi
s. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.