Microarray analysis of lncRNA expression in the human body. (A) The heatmap shows expression of the 121 most variably expressed lncRNAs (rows), defined as those with a coefficient of variation >0.2 across 31 cell/tissue types (columns). In the color scheme, yellow indicates higher expression, red indicates lower expression. (B) The intensity distribution of lncRNAs compared with protein-coding mRNAs. The data from GM12878 cells are shown, but similar results were observed in all samples. (C) A tree of expression correlation between samples; correlations were calculated using the expression of all lncRNAs in each sample. (D) The expression pattern of known lncRNAs. RNAs were manually curated from the literature. (Blue bars) Those RNA samples that do not contain any female component. Each row corresponds to a lncRNA transcript, and most lncRNA genes are represented on the array by several different transcript isoforms, resulting in multiple entries per lncRNA.
