A cure for Type 1 diabetes is a step closer after a new gene was discovered by scientists at the Children's Hospital of Philadelphia.
A cure for Type 1 diabetes is a step closer after a new gene was discovered by scientists at the Children's Hospital of Philadelphia.
Their breakthrough paves the way for a new drug treatment, meaning children would no longer be insulin-dependent.
Eventually, it may even allow physicians to screen newborns to predict those at high risk of developing the disease, allowing early intervention.
Scotland has the world's third-highest rate of Type 1 diabetes, which usually develops in childhood. The number of Scots with diabetes has risen from about 120,000 in 2003 to 173,000 today. Around 20% of these have Type 1, a condition where the insulin-producing cells of the pancreas are destroyed by an auto-immune response, leaving the patient dependent on insulin injections for life.
There is no known preventative measure that can be taken against Type 1 diabetes - diet and exercise cannot reverse it.
Scottish scientist Dr Struan Grant, 37, of the Children's Hospital of Philadelphia, was part of a team of scientists who identified a gene variant that raises a child's risk of the disease, formerly called "juvenile diabetes"
Scots-born Dr Grant, who trained at Aberdeen University and is now associate director of the hospital's Centre for Applied Genomics, said: "This is a highly significant discovery. The new gene offers new avenues for developing drug interventions which would be hugely helpful for children who are blighted by this devastating disease.
"The next step will be to target the gene and screen for compounds which can interfere with its role in destroying the pancreatic cells. The first clinical trials could begin in three to four years."
The ultimate aim is to develop an early intervention strategy for diabetes - designed to prevent children developing the disease in the first place.
"Now we've found this gene, we could develop a predictive test in combination with the other four genes previously found, to diagnose children who are at risk," said Dr Grant.
"This would go hand-in-hand with a drug treatment. Children would no longer have to inject insulin daily, and the drug might even prevent the pancreas cells being destroyed in the first place."
The investigators found the new gene by analysing the genomes of 1046 children with type 1 diabetes and comparing them to healthy controls.
They pinpointed a region on chromosome 16, occupied by a gene called KIAA0350, which was mutated in many children with the disease. The findings were published online yesterday in the journal Nature.
The scientists do not yet know the exact function of the protein the gene encodes. But the gene is known to be active almost exclusively in immune cells, including "Natural Killer" cells.
Research has predicted that it produces a protein that is located on the surface of immune cells - which may affect their ability to distinguish the body's own cells from invading bacteria.
Hakon Hakonarson, director of the centre, said: "Our hypothesis is that a special mutation in KIAA0350 may trigger an auto-immune response that activates these NK cells, in such a way that they attack and destroy the islet cells in the pancreas, resulting in type 1 diabetes.
"A particular version of the gene protects against this inappropriate auto-immune response, while a different version of the gene makes it more likely to happen."
The scientists will now study the exact role of the gene, to find out how it causes Type 1 diabetes and whether it interplays with the other four known disease genes.
As the project continues, the study team expects to identify additional genes - perhaps as many as 15 or 20 - thought to interact with each other in the disease.
Iain Frame, research manager at Diabetes UK, said: "While we don't know exactly what causes Type 1 diabetes, we know it is due to a combination of environmental and genetic factors and that the peak age for diagnosis is 10 to 14 years old.
"In time, these findings could enable us to develop more targeted treatments for young people."
Dr Grant said: "Our goal here is to create a database of the DNA profiles of 100,000 children, in order to identify disease genes in paediatric asthma, allergy, obesity, cancer and many other conditions."
