Objective: The role of human papillomavirus (HPV) in the development of cervical carcinoma has been clearlyestablished but other factors could be involved in cervicaltumorigenesis such as loss of heterozygosity (LOH) andmicrosatellite instability (MI). The aim of the present study was to investigate the genetic instability in cervicalcarcinoma tissues and provide evidence for discovering new tumor suppressor genes and screening diagnostic molecular marker of cervical carcinoma. Methods: Fifty primarycervical carcinoma samples from high-incidence area were analyzed by PCR for HPV16 infection, LOH andmicrosatellite instability. Results: HPV16 was detected in88% of the cases. Sixty-six percent of total cases showed LOH with no more than 3 different loci per case. Thehighest frequency of the allelic loss was found in D18S474 (18q21, 40.5%). MI was detected in 4 cases (8%) only.Conclusion: Different percentages of LOH on specificchromosomal regions were found and MI was veryinfrequent in cervical carcinoma. The putative suppressorgene(s) could be located on specific chromosome regionssuch as 18q, and genetic instability could be involved in cervical tumorigenesis. Objective: The role of human papillomavirus (HPV) in the development of cervical carcinoma has been clearly established, but other factors could be involved in cervical tumorigenesis such as loss of heterozygosity (LOH) andmicrosatellite instability (MI). The aim of the present study was to investigate the genetic instability in cervical cancer tissues and provide evidence for discovering new tumor suppressor genes and screening diagnostic molecular markers of cervical carcinoma. Methods: Fifty primarycervical carcinoma samples from high-incidence area were analyzed by PCR for HPV 16 infection, LOH and microsatellite instability. Results: HPV16 Six was-six percent of the total cases showed LOH with no more than 3 different loci per case. Thehighest frequency of the allelic loss was found in D18S474 (18q21, 40.5%). MI was detected in 4 cases (8%) only.Conclusion: Different percentages of LOH on specific chromosomal regions were found and MI was veryinfquentquent in ce The putative suppressor gene (s) could be located on specific chromosome regionssuch as 18q, and genetic instability could be involved in cervical tumorigenesis.