A new study has revealed a link between type-2 diabetes and a gene that produces an enzyme present in saliva which breaks down starch.
The research supports the idea that possessing additional copies of this gene may offer protection against type 2 diabetes. If subsequent studies confirm a clear correlation between the number of gene copies and the disease, genetic testing could be introduced at birth to predict individual susceptibility.
Researchers from Cornell University in the United States conducted the study, published on July 3 in the journal PLOS One and reported by EurekAlert.
Angela Poole, assistant professor of molecular nutrition at Cornell, said: ‘Knowing you face an increased risk of diabetes from birth could influence early life and daily decisions, potentially preventing the disease’s development later.’
Type 2 diabetes causes elevated blood glucose levels, resulting from insulin resistance or insufficient insulin production in the pancreas. Major contributing factors include excess weight and physical inactivity.
Individuals may have between two and twenty copies of the gene encoding the salivary enzyme amylase (AMY1).
Salivary amylase breaks down starch into sugars to initiate digestion. Dr Poole suggests that during starch consumption, the body senses glucose, prompting those with a higher AMY1 copy number to secrete insulin — the hormone regulating blood glucose, deficient in diabetes patients — more rapidly, producing a protective effect.
She added: ‘People with fewer copies are likely more vulnerable to type 2 diabetes.’
Dr Poole emphasised that starch intake also plays a role. To fully address these questions, future research must control diet, monitor participants over a long period and include a large sample size.
