Triploidy--Observations in 154 Diandric Cases.

Hydatidiform moles (HMs) are abnormal human pregnancies with vesicular chorionic villi, imposing two clinical challenges; miscarriage and a risk of gestational trophoblastic neoplasia (GTN). The parental type of most HMs are either diandric diploid (PP) or diandric triploid (PPM). We consecutively collected 154 triploid or near-triploid samples from conceptuses with vesicular chorionic villi.

Imprinted Genes on Chromosome 6 Are Unlikely to Cause Hydatidiform Mole. A Report of Two Cases.

Background: Hydatidiform moles are associated with an excess of paternal genome set(s) or abnormal imprinting of multiple imprinted genes. However, it appears unlikely that all imprinted genes are relevant for the pathogenesis of a hydatidiform mole.

Cases: We studied two rare cases of triploid, diandric moles that were tetrasomic for chromosome 6.