Project description:Mutations in components of the subcortical maternal complex (SMC) of the human oocyte are enigmatically associated with DNA methylation abnormalities specifically at imprinted genes in conceptuses, but the developmental timing, genomic extent and mechanistic details of these defects are unknown. Here, we show, by single-cell bisulphite sequencing, that mutation in human KHDC3L that causes recurrent hydatidiform mole results in a genome-wide deficit of de novo methylation in oocytes.
Project description:Maternal-effect mutations in components of the subcortical maternal complex (SCMC) of the human oocyte can cause early embryonic failure, gestational abnormalities and recurrent pregnancy loss. Enigmatically, they are also associated with DNA methylation abnormalities at imprinted genes in conceptuses, in the devastating gestational abnormality biparental complete hydatidiform mole (BiCHM) or in multi-locus imprinting disease (MLID). However, the developmental timing, genomic extent and mechanistic basis of these imprinting defects are unknown. Here, we studied methylation level of a women reported with familial recurrent hydatidiform mole and multiple pregnancy loss. Genotype analysis revealed homozygous mutation in KHDC3L. We obtained biparental mole from patient (Patient D) and compared it’s whole-genome methylation profile with respect to control placentas and sporadic mole (AnCHM) using Infinium MethylationEPIC BeadChip (WG-317-1001, Illumina). We also used endometrium samples from their respective mother for the comparison purposes. Molar conceptuses were observed with methylation defects at genome-wide level and profound loss of methylation at multiple genome-derived differentially methylated regions (gDMRs) confirming MLID.
Project description:Imprinted genes are critical for normal human growth and neurodevelopment. We developed a strategy to identify new DNA differentially methylated regions (DMRs), a hallmark of imprinted genes. Using genome-wide methylation profiling, candidate DMRs were selected by identifying CpGs with putative allelic differential methylation in normal biparental tissues. In parallel, we looked for parent of origin-specific DNA methylation patterns in paternally derived human androgenetic complete hydatidiform mole (AnCHM), and maternally derived mature cystic ovarian teratoma (MCT). Using this approach, we found known DMRs associated with imprinted genomic regions as well as new DMRs for known imprinted genes, NAP1L5 and ZNF597. Most importantly, novel candidate imprinted genes were identified. The paternally methylated DMR for one candidate, AXL, a receptor tyrosine kinase, was validated by methylation analyses in humans. Further validation in mouse embryos showed that Axl was expressed preferentially from the maternal allele in a DNA methylation–dependent manner. We have analyzed 3 androgenetic complete hydatidiform mole (AnCHM), 16 white blood cell (WBC), 1 mature cystic ovarian teratoma (MCT), 5 placenta, and 1 lymphoblastoid cell line paternal UPD4 sample
Project description:Patients with molar pregnancy are at risk of developing persistent trophoblastic disease (PTD). Previous study indicated that PTD risk was not related to evacuation time of hydatidiform mole (HM), leading to our hypothesis that HM might be pre-programmed before evacuation to determine the PTD risk. Considering the similarity between PTD and tumorigenesis, we investigated the methylation alterations in PTD conceptus using reduced representation bisulfite sequencing (RRBS), in order to identify potential predictors for PTD.
Project description:Copy number variations (CNVs) constitute the largest portion of the human genome variation. We determined a genome-wide high resolution SNP/CNV haplotype structure of Asians, by analyzing a collection of complete hydatidiform moles (CHMs) of Japanese, using high-density DNA arrays. CHMs are tissues carrying duplicated haploid genomes derived from single sperms, and are suitable material for the detection of CNVs, because they are expected to reveal greater signal to noise ratio in hybridization experiments. Also, the absence of heterozygosity ensures straightforward CNV interpretation without being bothered by overlapping CNV segments. We genotyped 100 CHM genomes using Affymetrix SNP 6.0 and Illumina 1M-duo, created a definitive haplotype map including 1.7 million SNPs and 2339 CNV region (CNVR) that is presented as D-HaploDB Phase 4.1. Illumina Human1M-Duov3 BeadChip analyses were performed according to the manufacturer's directions on DNA extracted from 97 complete hydatidiform moles (CHMs) tissues collected throughout Japan.
Project description:We reported a kind of new haploid embryonic stem cell, human haploid androgenetic embryonic stem cell, which kept the sperm characteristic epigenetic modification patterns for imprinting genes. In this study, two human haploid androgenetic embryonic stem cell lines (ha-AGHESC) and two human haploid parthenogenetic embryonic stem cell lines (ha-PGHESC) with somatic control and diploid HESC control, were processed with RNA-sequencing (RNA-seq) and whole genome bisulfite sequencing (WGBS). We showed that the reconstructed semi-clone HESCs were similar to the diploid HESC in transcriptome and the methylome especially related to the known human imprinting genes. The raw data of WGBS and bulk RNA-seq are deposited at Genome Sequence Archive (GSA) of Human with accession number HRA004100.
Project description:Androgenetic induced pluripotent stem cells (AgHiPSCs) were generated from androgenetic fibroblasts derived from a complete hydatidiform mole. AgHiPSCs can be used in regenerative medicine, for analysis of genomic imprinting, to study imprinting-related development, and for disease modeling in humans. To investigate the pluripotency state of AgHiPSCs, we analyzed their cellular and molecular characteristics (morphology, RT-PCR, qPCR, immunochemistry, and differentiation capacity in vitro and in vivo). We tested the DNA methylation status of imprinted genes using bisulfite sequencing and demonstrated the androgenetic identity of AgHiPSCs.
Project description:The naked mole-rat (NMR; Heterocephalus glaber) has recently gained considerable attention in the scientific community for its unique potential to unveil novel insights in the fields of medicine, biochemistry, and evolution. NMRs exhibit unique adaptations that include protracted fertility, cancer resistance, eusociality, and anoxia. This suite of adaptations is not found in other rodent species, suggesting that interrogating conserved and accelerated regions in the NMR genome will find regions of the NMR genome fundamental to their unique adaptations. However, the current NMR genome assembly has limits that make studying structural variations, heterozygosity, and non-coding adaptations challenging. We present a complete diploid naked-mole rat genome assembly by integrating long-read and 10X-linked read genome sequencing of a male NMR and its parents, and Hi-C sequencing in the NMR hypothalamus (N=2). Reads were identified as maternal, paternal or ambiguous (TrioCanu). We then polished genomes with Flye, Racon and Medaka. Assemblies were then scaffolded using the following tools in order: Scaff10X, Salsa2, 3d-DNA, Minimap2-alignment between assemblies, and the Juicebox Assembly Tools. We then subjected the assemblies to another round of polishing, including short-read polishing with Freebayes. We assembled the NMR mitochondrial genome with mitoVGP. Y chromosome contigs were identified by aligning male and female 10X linked reads to the paternal genome and finding male-biased contigs not present in the maternal genome. Contigs were assembled with publicly available male NMR Fibroblast Hi-C-seq data (SRR820318). Both assemblies have their sex chromosome haplotypes merged so that both assemblies have a high-quality X and Y chromosome. Finally, assemblies were evaluated with Quast, BUSCO, and Merqury, which all reported the base-pair quality and contiguity of both assemblies as high-quality. The assembly will next be annotated by Ensembl using public RNA-seq data from multiple tissues (SRP061363). Together, this assembly will provide a high-quality resource to the NMR and comparative genomics communities.
Project description:The naked mole-rat (NMR; Heterocephalus glaber) has recently gained considerable attention in the scientific community for its unique potential to unveil novel insights in the fields of medicine, biochemistry, and evolution. NMRs exhibit unique adaptations that include protracted fertility, cancer resistance, eusociality, and anoxia. This suite of adaptations is not found in other rodent species, suggesting that interrogating conserved and accelerated regions in the NMR genome will find regions of the NMR genome fundamental to their unique adaptations. However, the current NMR genome assembly has limits that make studying structural variations, heterozygosity, and non-coding adaptations challenging. We present a complete diploid naked-mole rat genome assembly by integrating long-read and 10X-linked read genome sequencing of a male NMR and its parents, and Hi-C sequencing in the NMR hypothalamus (N=2). Reads were identified as maternal, paternal or ambiguous (TrioCanu). We then polished genomes with Flye, Racon and Medaka. Assemblies were then scaffolded using the following tools in order: Scaff10X, Salsa2, 3d-DNA, Minimap2-alignment between assemblies, and the Juicebox Assembly Tools. We then subjected the assemblies to another round of polishing, including short-read polishing with Freebayes. We assembled the NMR mitochondrial genome with mitoVGP. Y chromosome contigs were identified by aligning male and female 10X linked reads to the paternal genome and finding male-biased contigs not present in the maternal genome. Contigs were assembled with publicly available male NMR Fibroblast Hi-C-seq data (SRR820318). Both assemblies have their sex chromosome haplotypes merged so that both assemblies have a high-quality X and Y chromosome. Finally, assemblies were evaluated with Quast, BUSCO, and Merqury, which all reported the base-pair quality and contiguity of both assemblies as high-quality. The assembly will next be annotated by Ensembl using public RNA-seq data from multiple tissues (SRP061363). Together, this assembly will provide a high-quality resource to the NMR and comparative genomics communities.