Genome-wide DNA methylation analysis of diploid hydatidiform moles with androgenetic or biparental genomic origin

Only very few studies have investigated methylation patterns of different types of hydatidiform moles (HMs). Methylation patterns of androgenetic HMs (AnHMs) are abnormal due to the fact that the nuclear genome in AnHMs is inherited from the father, only. Diploid biparental HMs (BiHM) have been suggested to display the same methylation patterns of imprinted genes as AnHMs, and the methylation patterns are suspected to be a consequence of a failure to establish maternal methylation at multiple genome-wide loci. We have investigated the methylation patterns of AnHMs, BiHM-like placentas with a chr. 11p15.5 deletion and a BiHM from a woman with NLRP7 mutations and compared these to methylation patterns of normal placentas. Using the Next Generation Sequencing (NGS) technique Reduced Representation Bisulfite Sequencing (RRBS) we instigated the genome-wide CpG methylation of 32 samples, including nine normal placentas, 20 androgenetic diploid HMs (AnHMs), and three diploid biparental HMs/HM-like placentas. This dataset contains RRBS data from 12 samples, including the nine normal placentas and the three diploid biparental HMs/HM-like placentas.The RRBS data from 20 androgenetic diploid HMs (AnHMs) was deposited in GSE65881:http://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE65881 A total of 32 human placentas were analysed. Nine normal placentas were used as negative controls in comparison with 20 androgenetic diploid HMs (AnHMs), and three diploid biparental HMs/HM-like placentas. The biparental HMs/HM-like placentas were of two different types: One BiHM originated from a woman that were homozygous for a splice-site mutation in NLRP7 and that had familial recurrent BiHM (sample131,BiHM/NLRP7mut). Two biparental HM-like placentas were both heterozygous for a terminal deletion on chr. 11 with breakpoint in 11p15.5 (sample101 and sample635, BiHM/del11p15.5). GSE67412 represents the RRBS data from 9 normal placentas and three diploid biparental HMs/HM-like placentas.