Found in Translation: A Type 1 Diabetes Genetic Risk Score Applied to Clinical Diagnosis

Potential use of the type 1 diabetes GRS described here in challenging clinical scenarios. The typical situation involves newly diagnosed diabetes in a young patient (20–40 years of age). A lean body habitus, particularly in people of European descent, would usually point toward type 1 diabetes (or more rarely monogenic diabetes), whereas an obese patient, particularly of African, Hispanic, Middle Eastern, or South Asian ancestry, is more likely to have type 2 diabetes. The presence of autoantibodies and low or undetectable C-peptide would confirm type 1 diabetes in the lean patient, and the absence of autoantibodies and normal or high levels of C-peptide would confirm type 2 diabetes in the obese patient. Where autoantibodies and C-peptide results seem counterintuitive, the T1D GRS may help guide the diagnosis toward or away from type 1 diabetes, particularly if very high (>0.280) or very low (<0.234) (see text for details). T1D, type 1 diabetes; T2D, type 2 diabetes; MODY, maturity-onset diabetes of the young.