Dataset Information

Definitive SNP/CNV haplotype map of Asians determined using a collection of complete hydatidiform moles (Affymetrix)

ABSTRACT: Copy number variations (CNVs) are abundant, possibly variable among populations, and can confer various phenotypic variations such as risk to complex disease. 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 that originated from single sperm, and have advantages as materials over conventional diploid cells in detecting CNVs by hybridization, because greater S/N ratios are expected, and overlapping CNV segments are independently detected without being bothered by possible heterozygous situations. Overall occupancy of CNV segments per haploid found here was at a level similar to previous reports. Approximately a half of our polymorphic CNV regions have not been described in the previous report for Asians, but the frequencies of most of these new CNV regions were low. The limited number of examined samples is likely to be the reason that they have escaped detection in the previous report. Many common CNV regions are resolvable to clusters of CNV segmets (that is, CNV events) on the basis of mutual overlap of the segments. The similarity of haplotype backgrounds surrounding different CNV events within the same CNV regions suggests that ancestral recurrences of CNV events were predominantly haplotype preferential.

ORGANISM(S): Homo sapiens

PROVIDER: GSE18642 | GEO | 2010/05/17

SECONDARY ACCESSION(S): PRJNA123815

REPOSITORIES: GEO

ACCESS DATA

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

Project description:Copy number variants (CNVs) reshape gene structure, modulate gene expression, and contribute to significant phenotypic variation. Previous studies have revealed CNV patterns in natural populations of Drosophila melanogaster and suggested that selection and mutational bias shape genomic patterns of CNV. While previous CNV studies focused on heterogeneous strains, here we established a number of second-chromosome substitution lines to uncover CNV characteristics when homozygous. The percentage of genes harboring CNVs is higher than found in previous studies. More CNVs are detected in homozygous than heterozygous substitution strains, suggesting the comparative genomic hybridization arrays underestimate CNV owing to heterozygous masking. We incorporated previous gene expression data collected from some of the same substitution lines to investigate relationships between CNV gene dosage and expression. Most genes present in CNVs show no evidence of increased or diminished transcription, and the fraction of such dosage-insensitive CNVs is greater in heterozygotes. More than 70% of the dosage-sensitive CNVs are recessive with undetectable effects on transcription in heterozygotes. A deficiency of singletons in recessive dosage-sensitive CNVs supports the hypothesis that most CNVs are subject to negative selection. On the other hand, relaxed purifying selection might account for the higher number of protein-protein interactions in dosage insensitive CNVs than in dosage-sensitive CNVs. Dosage-sensitive CNVs that are up-regulated and down-regulated coincide with copy number increases and decreases. Our results help clarify the relation between CNV dosage and gene expression in the D. melanogaster genome. To determine copy number variation, the genomic DNA from five homozygous and two heterozygous second chromosome substitution lines were extracted and compared to another second chromosome substitution line. Gene expression levels can be referred to at Series GSE12191 (Lemos et al. (2008) PMID:18791071).

Dataset Information

Definitive SNP/CNV haplotype map of Asians determined using a collection of complete hydatidiform moles (Affymetrix)

Dataset's files

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets