With the present study, we investigated whether elevated levels of ALT and GGT in the serum were associated with IFG through cross-sectional and longitudinal analysis, and we found that IFG development did indeed significantly increase according to serum ALT and GGT quartiles after we adjusted for established diabetes risk factors (age, gender, BMI, log-transformed alcohol consumption, smoking status, hypertension, and hyperlipidemia), and novel risk factor (uric acid). This evidence concerns the gene GPT and diabetes mellitus.