McGill discovery offers hope in diabetes
Another step on the road to a cure for diabetes may give hope to
the world’s 171 million diabetes sufferers, thanks to collaboration
between teams from Ď㽶ĘÓƵ and the University of
California at San Francisco (UCSF). Diabetes is a chronic condition
that occurs when the pancreas does not produce enough insulin
because of the destruction or dysfunction of small clusters of
cells, known as islets of Langerhans. However, the rest of the
pancreas, which produces digestive enzymes (the exocrine system),
remains intact and functioning.
It is known that during embryonic development, and in all
likelihood throughout life, exocrine cells can transform to become
islet cells and begin secreting insulin. Finding a way to activate
this transformation holds great promise in terms of improved
treatments for diabetes, but the genes involved are not thoroughly
understood.
A team led by Constantin Polychronakos, of McGill’s Endocrine
Genetics Laboratory at The Children’s Hospital site of the Research
Institute of the Ď㽶ĘÓƵ Hospital Centre (RI-MUHC), used
state-of-the-art technologies such as capture microarrays and
highly parallel sequencing to examine a previously unstudied gene
called RFX6. The team discovered mutations in this gene and found
that these mutations are the cause of a rare syndrome of neonatal
diabetes involving the complete absence of islets of Langerhans.
The work is set to be published in the journal Nature.
Collaborator Michael German, of UCSF, showed the same outcome in
animals – that mice, whose RFX6 genes had been artificially
disrupted, develop exactly the same syndrome as found in human
neonatal diabetes cases. Although this syndrome is an extremely
rare cause of diabetes, knowledge of the gene involved may benefit
all people suffering from diabetes.
“This discovery brings us closer to one day finding a cure for
diabetes. Now that we know the RFX6 gene is crucial in the process
of insulin production, the door is open to finding a cure through
gene therapy or therapeutics that will create new islets out of
cells from the rest of the pancreas,” said Polychronakos.
The study was funded by the Juvenile Diabetes Foundation.