Genetic origin analysis of hydatidiform mole and non-molar abortion using the polymerase chain reaction method.

OBJECTIVES

The study attempts to determine the genetic origin of hydatidiform mole and non-molar abortion using the polymerase chain reaction (PCR) method, and reevaluates this method as a possible diagnostic tool for hydatidiform mole.

MATERIAL AND METHODS

A total of 71 cases which consists of 21 complete hydatidiform moles, three partial hydatidiform moles, and 47 non-molar abortions were investigated. The genetic origin was analyzed by the PCR method applied to the variable number of tandem repeat regions of the Apolipoprotein B gene, the human type-II collagen gene, and the probe YNZ22. Chromosomal analysis was also performed.

RESULTS

Genetic origin was determined in 58 out of 71 cases (83.1%). All of the complete hydatidiform moles were androgenic, having only paternal alleles. On the other hand, all the partial hydatidiform moles and non-molar abortions revealed clear biparental contribution. Besides triploid partial hydatidiform moles, one non-molar abortion showed two paternal and one maternal complements.

CONCLUSIONS

Our results were compatible with the classical theory of androgenic origin of complete hydatidiform mole; only complete hydatidiform mole is caused by androgenesis. We also found no complete hydatidiform mole of biparental origin. In conclusion, this PCR method brings a new aspect of genetic origin in the diagnosis of trophoblastic disease. It would be interesting to explore how morphologic subgrouping and genetic origin relate to the prognosis of trophoblastic disease.