A new Cornell University study brings additional clarity to the relationship between Type 2 diabetes and genes that express a salivary enzyme that breaks down starch.
If researchers do eventually prove a clear association between AMY1 copy number and diabetes, it could lead to genetically testing people at birth to predict their susceptibility.
Researchers collected measurements from study participants of amylase activity very early in the morning after fasting and in the evening. They found that morning readings were much lower than they were in the evenings.
When they compared participants, they found that salivary amylase activity was higher for each additional copy of AMY1 in those with Type 2 diabetes or prediabetes, compared to those without either.
The findings have led Angela Poole, assistant professor of molecular nutrition, to suspect that a higher copy number of AMY1 genes may be protective, though more study is needed to verify it.
Since amylase breaks down starch into sugars, common sense would suggest that a higher AMY1 copy number would increase blood glucose and be detrimental to people with Type 2 diabetes. Poole suspects that during chewing of starch, the body senses the glucose, and it causes people with a higher AMY1 copy number to release insulin sooner, leading to a protective effect. Gut microbes may also play a role.
“I suspect that people with a lower copy number are at higher risk for Type 2 diabetes,” Poole said. But she added, it also depends on how much starch they eat.
Reference: Devarakonda SLS, Ren J, Poole AC (2025) The association between salivary amylase gene copy number and enzyme activity with type 2 diabetes status. PLoS One 20(7): e0324660. https://doi.org/10.1371/journal.pone.0324660
Disclaimer: This website is primarily for healthcare professionals. The content here does not replace medical advice and should not be used as medical, diagnostic, endorsement, treatment, or prescription advice. Medical science evolves rapidly, and we strive to keep our information current. If you find any discrepancies, please contact us at corrections@medicaldialogues.in. Read our Correction Policy here. Nothing here should be used as a substitute for medical advice, diagnosis, or treatment. We do not endorse any healthcare advice that contradicts a physician's guidance. Use of this site is subject to our Terms of Use, Privacy Policy, and Advertisement Policy. For more details, read our Full Disclaimer here.
NOTE: Join us in combating medical misinformation. If you encounter a questionable health, medical, or medical education claim, email us at factcheck@medicaldialogues.in for evaluation.