Researchers have found that missteps in a basic cellular process, RNA splicing, is the culprit behind a class of rare neurological disorders manifested by intellectual disability and stunted development.

In RNA splicing, nascent RNA molecules are modified and edited so they can then go about the business of synthesizing proteins. Incorrect splicing of RNA, however, impairs cellular function.

Qingqing Wang, a doctoral student in systems biology at Harvard Medical School, found that genome-wide splicing errors were caused by mutations in a gene called PQBP1, which encodes a protein that has previously been linked to Renpenning syndrome, an X-linked cognitive disorder.

“This is one of the first studies to show the effect of RNA processing on neural defects across the whole genome,” said Pamela Silver, HMS professor of systems biology and senior study author.

These findings were published on March 15 in the journal Genes and Development.