Project description:In order to test the hypothesis that X chromosome inactivation shows sequence specificity, we have analysed the spread of XCI into autosomal chromatin by performing DNA methylation profiling in six unbalanced X;autosome translocations. Using promoter hypermethylation as an epigenetic signature of XCI, we have determined the inactivation status of 1,050 autosomal genes after translocation onto the inactive X. By performing a comparative sequence analysis of autosomal genes that are either subject to or escape the X inactivation signal, we identified a number of common repetitive elements, including LINEs, and DNA motifs that are significantly enriched around inactive autosomal genes. We show that these same motifs predominantly map to L1P elements, are significantly enriched on the X chromosome versus the autosomes, and also occur at higher densities around X-linked genes that are subject to X inactivation compared to those that escape X inactivation. These results are consistent with a potential causal relationship between DNA sequence features such as L1s and the spread of XCI, lending strong support to Mary Lyon's 'repeat hypothesis'. Genome-wide measurement of CpG methylation levels by hybridizing bisulphite-converted DNA to Infinium HumanMethylation450 BeadChips. Eight DNA samples extracted from individuals carrying X;autosome translocations were processed according to manufacturer's recommended protocols, and array data processed using the Methylation Module of GenomeStudio v1.8 software with default parameters.

2013-09-13 | E-GEOD-50837 | biostudies-arrayexpress

DNA methylation profiling in X;autosome translocations supports a role for L1 repeats in the spread of X chromosome inactivation

2013-09-13 | GSE50837 | GEO

Abnormal X: autosome ratio, but normal X chromosome inactivation in human triploid cultures.

Project description: Not available

| S-EPMC1526452 | biostudies-literature

Chromosome landmarks and autosome-sex chromosome translocations in Rumex hastatulus, a plant with XX/XY1Y2 sex chromosome system.

Project description: Not available

| S-EPMC4430600 | biostudies-literature

Premature ovarian insufficiency is associated with global alterations in the regulatory landscape and gene expression in balanced X-autosome translocations.

Project description: Not available

| S-EPMC10197467 | biostudies-literature