Six groups of ncRNAs based on expression patterns in human, murine, and chicken tissues. A. Representative ncRNA expression patterns from each of the six groups of ncRNAs. The expression of 117 rhesus monkey ncRNAs was examined by northern blotting using 5 μg aliquots of total RNA from monkey spleen, brain, kidney, liver, heart, and skeletal muscle. Total RNA from human, murine, and chicken skeletal muscle were included in each RNA blot to test expression in different species. Based on northern blot analysis, the expression patterns in various species could be classified into six types. One representative ncRNA from each of the six groups is shown. All ncRNAs are labeled as Name_size on the left side of each northern blot. B. Summary of ncRNA numbers in each of the six groups. * The total number of the probes is less than the total number of ncRNAs because several ncRNA members in the same snoRNA family can be recognized by the same probe.