transcriptome may be vastly more complex than currently appreciated when very lowly expressed transcripts are considered [7]. It is possible that some of these are functional transcripts despite their apparent low expression, perhaps having brief bursts of expression during stages of the cell cycle or functioning in single cells in a heterogeneous population as has been previously observed [14]. Therefore, while we have provided the most complete lincRNA catalog to date, there may be additional lowly expressed, yet potentially functional lincRNAs that were excluded here.
