AMY1 Gene Copy Number May Protect Against Type 2 Diabetes

By Stayinghealthy !
Having more copies of the gene expressing salivary amylase may have a protective effect against type 2 diabetes (Shutterstock).
Having more copies of the gene expressing salivary amylase may have a protective effect against type 2 diabetes (Shutterstock)./ Aljazeera.net


Recent research suggests that individuals with a higher number of copies of the AMY1 gene—which codes for salivary amylase—may have a lower risk of developing type 2 diabetes.

 New Scientific Findings from Cornell University

A team led by Angela C. Poole at Cornell University analyzed saliva & genetic data and found strong links between AMY1 copy number (CN), salivary amylase activity (SAA), and type 2 diabetes or prediabetes.


  • Participants had between 2 to 20 AMY1 copies .
  • Saliva collection time affects enzyme levels—morning readings were consistently lower, underscoring the importance of consistent sampling .
  • For people with type 2 diabetes or prediabetes, each extra copy of AMY1 was associated with a ~43% higher SAA, compared to a ~14% increase in healthy individuals—PLOS One, July 2, 2025 .

This suggests a biological mechanism: during starch digestion, increased salivary amylase releases glucose earlier, prompting a faster insulin response, which may help regulate blood sugar and protect against type 2 diabetes .

Clinical Implications & Future Research

If confirmed in larger, long-term studies, measuring AMY1 copy number could become part of early genetic screening to assess diabetes risk from birth:

  • Early identification could enable personalized dietary and lifestyle interventions from childhood onward.
  • Further studies need to control for starch intake, monitor participants over years, and include larger groups .
  • A new PLOS One study confirmed that laboratory methods (qPCR vs ddPCR) are comparable and that diurnal timing matters in measuring enzyme activity .

Global Genetic & Microbiome Context

Gene–diet interactions shape AMY1 CN across cultures. Agricultural populations with high-starch diets—like the Japanese—tend to have more AMY1 copies, showing evolutionary adaptation . Microbiome studies also link high AMY1 CN with gut bacteria that may influence metabolic health .

Bottom Line

High AMY1 gene copy number may offer a natural defense against type 2 diabetes, especially for those consuming starch‑rich diets. Early genetic testing combined with lifestyle modifications could become a powerful prevention strategy.


References and further reading

  1. Devarakonda, S. L. S., Ren, J., Poole, A. C., et al. (2025). The association between salivary amylase gene copy number and enzyme activity with type 2 diabetes status . PLOS ONE, July 2, 2025.
  2. EurekAlert (2025). Study supports link between saliva enzyme gene and type 2 diabetes . Published by Cornell University, July 2, 2025.
  3. PubMed Entry: PMID: 40601572 . National Library of Medicine.
  4. Rukh, G. et al. (2022). Gene–diet interactions in salivary amylase and microbiome associations . Scientific Reports, Nature
  5. Wikipedia Contributors (2025). AMY1A – Amylase alpha 1 gene . Wikipedia, The Free Encyclopedia.