Objective: DNA analysis of different forms of gestational trophoblastic disease. Design: Retrospective clinical study. Setting: Slovak Center of Trophoblastic Disease, Bratislava, Slovak Republic. Methods: In the period of September 1993 to April 2003, eighty-nine cases of gestational trophoblastic disease were analysed. There were 22 cases of partial hydatidiform moles, 58 cases of complete hydatidiform mole, 5 cases of invasive mole and 4 cases of gestational choriocarcinomas. Southern hybridization and polymerase chain reaction were used for DNA analysis. Results: From 22 analyzed cases of partial hydatidiform moles 19 (86.4%) were triploid and 3 (13.6%) diploid ones. There were 58 cases of complete hydatidiform mole and out of them 29 (50%) were homozygous, 28 (48.3%) heterozygous, and in one case (1.7%) both paternal and maternal genome was detected. In 8 cases of heterozygous and in one case of homozygous complete hydatidiform mole occurred a malignant transformation to gestational choriocarcinoma. Conclusions: Molecular analysis can determine the nuclear DNA origin of complete hydatidiform mole and allow us to defi ne the patients with higher risk of malignant transformation usually to gestational choriocarcinoma.

        Key words: DNA analysis, gestational trophoblastic disease, hydatidiform mole, choriocarcinoma