Novel NLRP7 mutations in familial recurrent hydatidiform mole: are NLRP7 mutations a risk for recurrent reproductive wastage?
EUROPEAN JOURNAL OF OBSTETRICS & GYNECOLOGY AND REPRODUCTIVE BIOLOGY
Authors: Ulker, V.; Gurkan, H.; Tozkir, H.; Karaman, V.; Ozgur, H.; Numanoglu, C.; Gedikbasi, A.; Akbayir, O.; Uyguner, Z. O.
Abstract
Objective: Familial recurrent hydatidiform mole is an exceedingly rare clinical condition. Affected women are predisposed to molar pregnancies of diploid, biparental origin rather than androgenetic origin. At present, NLRP7 and KHDC3L (C6or (f) over bar 221) are the only genes known to be associated with familial recurrent hydatidiform mole. This study investigated the genetic dispositions in two large Turkish families with recurring molar conceptuses. Study design: Copy number variation analysis was performed followed by NLRP7 gene sequencing. The finding of a mono-allelic condition in one family led to investigation of the adjacent NLRP2 gene and recently associated KHDC3L gene. Sampled molar tissues were genotyped using microsatellite markers. Results: In one family, a homozygous single nucleotide insertion that caused a frameshift leading to an early stop codon, c.2940_2941insC (p.Glu981ArgfsX13), was identified in the affected sisters. In the other family, a heterozygous 60-kb deletion eliminating substantial portions of the NLRP2 and NLRP7 genes on one allele was found. Screening of NLRP2 and KHDC3L genes revealed no alterations that were considered to be pathological. Genotyping of six independent molar conceptions revealed that five were of diploid, biparental origin and one was of diandric, triploid origin. Conclusions: Two novel protein-truncating mutations in the NLRP7 gene were found to be associated with familial recurrent hydatidiform mole. Mutations in the NLRP7 gene causing recurrent biparental hydatidiform mole may also be associated with other forms of recurrent reproductive wastage. (C) 2013 Elsevier Ireland Ltd. All rights reserved.
Recurrent complete hydatidiform mole: where we are, is there a safe gestational horizon? Opinion and mini-review
JOURNAL OF ASSISTED REPRODUCTION AND GENETICS
Authors: Kalogiannidis, Ioannis; Kalinderi, Kallirhoe; Kalinderis, Michail; Miliaras, Dimosthenis; Tarlatzis, Basil; Athanasiadis, Apostolos
Abstract
Benign hydatidiform mole, complete or partial, is the most common type of gestational trophoblastic disease (GTD) characterised by excessive trophoblastic proliferation and abnormal embryonic development. Although most complete hydatidiform moles (CHMs) are diploid androgenetic, a few cases of CHMs are biparental, characterised by recurrence and familial clustering. In these rare cases, mutations in NLRP7 or KHDC3L genes, associated with maternal imprinting defects, have been implicated. Current data regarding future pregnancy options in hydatidiform moles are discussed and our opinion is presented based on an incidence that took place in our hospital with a woman with consecutive molar pregnancies. In recurrent hydatidiform moles, DNA testing should be performed and when NLRP7 or KHDC3L mutation are detected, oocyte donation should be proposed as an option to maximise woman's chances of having a normal pregnancy.