Polymorphisms (rs1801282, rs8192678, rs7903146) of peroxisome proliferator-activated receptor gamma (PPARG), peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PPARGC1A) and transcription factor 7-like 2 (TCF7L2) have recently been associated with different diseases, mainly type 2 diabetes. An assay using unlabeled probes and the LightCycler or Rotor-Gene instruments was developed for genotyping of these three polymorphisms. Asymmetric polymerase chain reaction was used, followed by melting analysis of the unlabeled probe/ssDNA amplicon duplex. Samples with the target genotypes were accurately detected and easily distinguishable. Thus, genotyping using unlabeled probes is a rapid, accurate and cost effective closed-tube method. These assays demonstrated 100% specificity and sensitivity for the identification of selected polymorphisms in PPARG, PPARGC1A and TCF7L2 genes.