Primate-specific microRNAs found

Israeli scientists have identified what may be the first microRNAs specific to primates, in research published online June 19 in Nature Genetics. They suggest these new microRNAs might mean that hundreds remain to be found in the human genome.

"Finding a group of genes that is specific to primates is very important for understanding our evolution, and bears significant diagnostic and therapeutic potential," lead researcher Isaac Bentwich, at Rosetta Genomics in Rehovot, told The Scientist.

MicroRNAs are single-stranded RNAs roughly 22 nucleotides long that regulate gene expression by binding to target gene mRNAs. The DNA sequence that codes for a microRNA gene includes the microRNA sequence and a nearby complementary sequence that, when transcribed, form a double-stranded RNA hairpin loop.

Past studies have identified 222 human microRNAs, of which scientists had confirmed the sequences of only 86 in humans. To uncover more, Bentwich and colleagues computationally folded the entire human ...