Diabetes Genes

Guidelines for Genetic Testing in MODY


The purpose of these criteria is to ensure that NHS resources are used effectively to diagnose monogenic diabetes. These new NHS England National Genomic Test Directory Testing Criteria for Rare and Inherited Disease (R141 Monogenic diabetes, R142 Glucokinase-related fasting hyperglycaemia and R143 Neonatal Diabetes) were published in October 2021 (https://www.england.nhs.uk/wp-content/uploads/2018/08/rare-and-inherited-disease-eligibility-criteria-v3-2.pdf.pdf). The criteria has been set to keep the positive rate of tests performed at 25% overall as it has been over the past decade of testing for monogenic diabetes. They will be reviewed and revised should there be any significant change to this pick-up rate.

The criteria apply to the proband (i.e. the first member of a family with diabetes to be tested).  Once a genetic diagnosis of monogenic diabetes has been confirmed in the proband, other family members will be eligible for testing of the familial variant.

Genetic testing for monogenic diabetes (R141 and R143) will only be performed on patients confirmed to have diabetes by laboratory blood glucose or HbA1c according to the WHO definition unless they meet criteria for Glucokinase related fasting hyperglycaemia (R142).

Testing indications:

  • Diabetes – Maturity-onset diabetes of the young (R141)
  • Glucokinase related fasting hyperglycaemia (R142)
  • Neonatal diabetes (R143)
  • Diabetes and non-autoimmune extra pancreatic features (R141)
  • Diabetes with severe insulin resistance (R141)


For further information, please contact Kevin Colclough, Principal Clinical Scientist at:

Exeter Genomics Laboratory
Royal Devon University Healthcare NHS Foundation Trust
Barrack Road

Email: rde-tr.betacellgenomics@nhs.net