Among the highest contributing proteins in the chosen components and peaks in diabetic nephropathy, impaired renal function and other diseases were the following: transthyretin, apolipoprotein C1 (apo C1), apolipoprotein A1 (apo A1) and cystatin C. The identities of these proteins were confirmed by immunoprecipitation and sequencing or western blots. This evidence concerns the gene APOC1 and diabetic kidney disease.