A complete hydatidiform mole (CHM) is an abnormal pregnancy with hyperproliferative vesicular trophoblast and no fetal development. Most CHM are sporadic and androgenetic, but recurrent HM have biparental inheritance (BiHM) with disrupted DNA methylation at differentially methylated regions (DMRs) of imprinted loci. Some women with recurrent BiHM have mutations in the NLRP7 gene on chromosome 19q13.42. Using bisulfite genomic sequencing at eight imprinted DMRs on DNA from two BiHMs, we found a pattern of failure to acquire or maintain DNA methylation at DMRs (PEG3, SNRPN, KCNQ1OT1, GNAS exon 1A) that normally acquire CpG methylation during oogenesis, but not at H19, which acquires CpG methylation during spermatogenesis. Secondary imprints at the GNAS locus showed variable abnormal patterns with both gain and loss of CpG methylation. We found novel missense and splice-site mutations in NLRP7 in women with non-familial recurrent BiHM. We identified and characterized a homozygous intragenic tandem duplication including exons 2 through 5 of NLRP7 that results in a predicted truncated protein in affected women of three unrelated Egyptian kindreds, suggesting a founder effect. Our findings firmly establish that NLRP7 mutations are a major cause of BiHM and confirm presence of a complex pattern of imprinting abnormalities in BiHM tissues.

Hu et al. (1996) and Laporte et al. (1997) recently proposed a novel contiguous gene syndrome of myotubular myopathy, abnormal male genital development and deletion in Xq28. We studied a family where two male infants, both deceased, had myotubular myopathy and intersexual genitalia. Using FISH we detected in the mother a hemizygous deletion including the myotubularin gene MTM1 and F18 (a gene of yet unknown function). DNA studies with STR-markers (short tandem repeats) within and flanking the deleted segment confirmed the deletion in the family and were used for prenatal diagnosis. Our findings confirm the existence of this novel contiguous gene syndrome and support that the deletion of the F18 gene, or a neighboring gene, may cause ambiguous genitalia or severe hypospadias in males. The mother had low muscle power and marked menstrual irregularities which may indicate that she is a manifesting carrier and that the deletion may include a gene (F18 or other) for gonadal function in females.

Objective Expanded carrier screening (ECS) assesses the risk of individuals and couples of having a child affected with a set of genetic conditions. Carriers have options available to optimize pregnancy outcomes based on personal values and preferences. The greatest range of options is available prior to pregnancy, therefore professional societies recommend this screening be performed preconception. This study aimed to assess awareness of, and interest in, ECS in women preconception. Additionally, it aimed to evaluate preferences for timing and location of education and availability of ECS. Methods A total of 260 nulliparous women from the general population were surveyed through Qualtrics, a national market research survey platform. Data were delineated using descriptive statistics. Results Of this cohort, 43.5% reported being aware of ECS prior to the survey and 77.8% indicated interest. Those previously aware were first informed by family, friends, or independent online research. Interest was primarily driven by a desire for reassurance and to make informed decisions about future pregnancies. Interested respondents indicated a willingness to request testing from providers. Participants showed a preference for education and access from a healthcare provider in person. Conclusion These findings provide insight regarding when and where to best educate and reach women prior to pregnancy about ECS to maximize pregnancy outcomes.

Objective: To evaluate the mutational spectrum of NLRP7 and KHDC3L (C6orf221) in women with sporadic and recurrent androgenetic complete hydatidiform moles (AnCHM) and biparental hydatidiform moles (BiHM) to address the hypothesis that autosomal recessive mutations in these genes are only or primarily associated with biparental hydatidiform moles. Method: We recruited 16 women with suspected recurrent and sporadic AnCHM and 5 women with suspected BiHM in addition to their reproductive partners into our study. We then sequenced the coding exons of NLRP7 and KHDC3L from DNA isolated from either blood or saliva from the study subjects. Results: Sequence analysis of NLRP7 and KHDC3L revealed previously described SNPs in patients with AnCHM. However in patients with BiHM, we identified a novel homozygous mutation and a previously described intragenic duplication of exon 2-5 in NLRP7, both of which are likely to be disease causing. We did not identify mutations in KHDC3L in patients with the either forms of HM. Conclusions: The absence of mutations in the women with AnCHM supports a role of NLRP7 or KHDC3L in BiHM only. The absence of mutations in KHDC3L in women with BiHM is consistent with its minor role in this disease compared to NLRP7, the major BiHM gene.