The Family Investigation of Nephropathy and Diabetes Study

Diabetic Nephropathy (DN) is undoubtedly a multifactorial disease, and a large proportion of patients affected with either type 1 or type 2 diabetes develop diabetic nephropathy and progress to end stage renal disease (ESRD). When poor prognostic factors such as hypertension and chronic hyperglycemia are aggressively treated, the rate of progression of diabetic nephropathy can be slowed. However, no interventions have been shown to reliably halt the progression of diabetic nephropathy. Numerous studies have suggested that genetic predisposition to diabetic nephropathy exists, but genes for nephropathy have not yet been isolated. It is anticipated that a comprehensive analysis of a large number of uniformly phenotyped ESRD families will be necessary to isolate genes for ESRD. Such a database of families may not be available at any single institution. The FIND study has established a centralized Genetic Analysis and Data Coordinating Center (GADCC) that, together with eight participating investigation centers (PICs), three minority recruitment centers, and the National Institute of Diabetes, Digestive and Kidney Diseases (NIDDK), will use the emerging high-throughput genetic technologies to enable identification of diabetic nephropathy susceptibility or protection genes. The charge of the consortium is to acquire sets of families with well-characterized diabetic nephropathy, establish a secure master FIND database, and perform a genome scan to identify chromosomal regions linked with diabetic nephropathy. The FIND study population includes participants from European American (EA), Native American (NA), African American (AA) and Mexican American (AA) populations. Two analytic approaches are utilized in FIND. The Family Study approach involves the enrollment of probands, affected or discordant sibling and their affected family members. Analytic methods include affected sibling pair (ASP), discordant sibling pair (DSP) affected relative pair (ARP), and discordant relative pair (DRP) linkage analyses for the Family Study. The Mapping by Admixture and Linkage Disequilibrium (MALD) approach involves the enrollment of probands and a population based control for both the AA and MA studies. In addition, a spousal control (diad) and when available, a child 18 years or older, will be recruited (triad)for the AA MALD study only.