RESUMO
<p><b>OBJECTIVE</b>To analyze the allelic loss of heterozygosity (LOH) in the region of chromosome 4p15.1-4q12 in nasopharyngeal carcinoma (NPC) patients with family history.</p><p><b>METHODS</b>Tumor cells and lymphocytes were obtained from paraffin-embedded biopsied tissue section by microdissection. LOH detections were carried out on 25 NPC patients with family history by PCR-based microsatellite polymorphism analysis using 7 pairs of microsatellite markers primers. The microsatellite loci located in 4p15.1-4q12 region. Genescan software was used to analyse LOH at each locus.</p><p><b>RESULTS</b>Ninety-two percent of NPC cases (23/25) with family history was showed at least one microsatellite marker of LOH. Higher frequencies of LOH were found at three loci: D4S238 (56%), D4S350 (50%), D4S1547 (50%). The minimal common region of deletion might be defined between D4S350 and D4S1547.</p><p><b>CONCLUSION</b>The higher incidence of LOH at D4S350 and D4S1547 suggests that there may be a potential tumor suppressor gene located in the two regions.</p>