Thu, 21 Aug 2008 22:24:35 BST CiteULike: jo_davies's Matigian http://www.citeulike.org/user/jo_davies/author/Matigian CiteULike.org en-gb Copyright © 2004-2008 citeulike.org http://www.citeulike.org/user/jo_davies/article/2747870 <i>Human molecular genetics, Vol. 16, No. 4. (15 February 2007), pp. 364-373.</i><br /><br />The expression level for 15,887 transcripts in lymphoblastoid cell lines from 19 monozygotic twin pairs (10 male, 9 female) were analysed for the effects of genotype and sex. On an average, the effect of twin pairs explained 31% of the variance in normalized gene expression levels, consistent with previous broad sense heritability estimates. The effect of sex on gene expression levels was most noticeable on the X chromosome, which contained 15 of the 20 significantly differentially expressed genes. A high concordance was observed between the sex difference test statistics and surveys of genes escaping X chromosome inactivation. Notably, several autosomal genes showed significant differences in gene expression between the sexes despite much of the cellular environment differences being effectively removed in the cell lines. A publicly available gene expression data set from the CEPH families was used to validate the results. The heritability of gene expression levels as estimated from the two data sets showed a highly significant positive correlation, particularly when both estimates were close to one and thus had the smallest standard error. There was a large concordance between the genes significantly differentially expressed between the sexes in the two data sets. Analysis of the variability of probe binding intensities within a probe set indicated that results are robust to the possible presence of polymorphisms in the target sequences. Replicated effects of sex and genotype on gene expression in human lymphoblastoid cell lines. AF McRae NA Matigian L Vadlamudi JC Mulley B Mowry NG Martin SF Berkovic NK Hayward PM Visscher Human molecular genetics, Vol. 16, No. 4. (15 February 2007), pp. 364-373. 2008-05-03T10:24:22-00:00 2007 Human molecular genetics 0964-6906 16 4 364 373 no-tag