Complete hydatidiform moles are composed of paternal chromosomes and maternal mitochondria

Spermatogonium-Derived Complete Hydatidiform Mole

A complete hydatidiform mole (CHM) is a conceptus with only sperm-derived chromosomes. Here, we report on a CHM with genomic DNA identical to that of the paternal somatic cells. The CHM developed in a woman who had undergone intrauterine implantation of a blastocyst obtained through in vitro injection of a presumed round spermatid into one of her oocytes. The CHM was genetically identical to peripheral white cells of her husband and contained no maternally derived nuclear DNA. We hypothesize that a spermatogonium, rather than a round spermatid, was inadvertently selected for the procedure. The CHM developed into a gestational trophoblastic neoplasia, which resolved after chemotherapy. (Funded by the Japan Society for the Promotion of Science.).

Which One Is More Prominent in Recurrent Hydatidiform Mole, Ovum or Sperm?

Recurrent hydatidiform mole is defined as episodes of two molar pregnancies in a female. Often, complete moles only derive androgenic nuclear genome. We described two cases with repeated molar pregnancies attempted to prevent future episodes by performing intracytoplasmic sperm injection (ICSI) and preimplantation genetic diagnosis (PGD) to assess genetic disorders. The first patient had previously six complete molar pregnancies and advised to carry out ICSI with ovum donation to achieve a normal pregnancy. The second case had previously five molar pregnancies and no XY embryos from the ICSI/PGD process. We had to (at the insistence of the patient) transfer XX embryos in this patient which resulted in a complete hydatidiform mole (CHM). Hence, available data based on our patients and previous studies demonstrated that oocyte might play a critical role in the pathophysiology of recurrent hydatidiform mole, while it has not been often considered.