A new study has revealed that human microRNAs, small non-coding RNA molecules that regulate gene expression, are linked to type 2 diabetes. This is the largest study to date that has looked into the relationship between diabetes-related microRNAs and human pancreatic islets. The findings were published in the Proceedings of the National Academy of Sciences on February 9.
The study’s corresponding authors, Praveen Sethupathy, a professor of biomedical sciences at Cornell University and Dr. Francis Collins, a former director of the National Institutes of Health and a senior investigator at the National Human Genome Research Institute, had access to a network that supplied nearly 65 human pancreatic islet samples for the study. This allowed the researchers to use large-scale, next-generation sequencing to identify at least 14 pancreatic islet microRNAs that are implicated in human type 2 diabetes.
The relatively large sample size helped to reveal the extent of variation in the number of microRNAs in the islets across the human population. The researchers also had genetic information on all the patients, which helped them determine a handful of genomic loci underlying variability in microRNA expression. One of these loci was found in the same area of the genome that is associated with type 2 diabetes-related traits, which could suggest a novel mechanism for how type 2 diabetes develops.
Some of the most altered microRNAs in islets from individuals with type 2 diabetes were consistent with those found in previous rodent studies, but there were also some notable differences. These differences represent interesting candidates to investigate further in human models of pancreatic islets.