Novel mutations of maternal effect gene thyroid hormone receptor interactor 13 involved in biparental complete hydatidiform mole.

RATIONALE: Biparental complete hydatidiform mole (BiCHM) is a rare form of molar pregnancy, frequently associated with familial recurrence, whose mechanism was historically unclear. It is classically diploid with biparental inheritance, but manifests as a complete hydatidiform mole (CHM). Cytogenetic studies suggested a link to maternal mutations in imprinted genes NOD-like receptor family, pyrin domain containing 7 or Kelch helper domain containing 3-like within the oocyte. This case reports a novel gene association. PATIENT CONCERNS: A 43-year-old woman presented with a history of recurrent abnormal pregnancies: 2 CHM and 1 spontaneous abortion following an intracytoplasmic sperm injection (ICSI)-assisted conception. DIAGNOSES: Short tandem repeat polymorphism analysis of products of conception (including both CHM and the aborted ICSI pregnancy) revealed all 3 were biparental triploids derived from the patient and her husband. Whole-exome sequencing of the patient's family identified that the patient carries compound heterozygous mutations (c.-82G > A [paternally inherited] and c.*106G > A [maternally inherited]) in the autosomal recessive gene thyroid hormone receptor interactor 13 (TRIP13), confirmed by Sanger sequencing. INTERVENTIONS: Given the genetic findings and history of recurrent BiCHM, ovarian donation or adoption was recommended as the treatment strategy to achieve a normal pregnancy. OUTCOMES: The genetic diagnosis was established, informing future reproductive counseling and management options. LESSONS: To our knowledge, this is the first report linking biallelic TRIP13 mutations to recurrent BiCHM, indicating its potential role in the pathogenesis. ICSI-assisted reproduction did not improve pregnancy outcomes. Ovarian donation or adoption was recommended.