title: The Family Investigation of Nephropathy and Diabetes (FIND): design and methods.
abstract: BACKGROUND
  The Family Investigation of Nephropathy and Diabetes (FIND) is a multicenter study designed to identify genetic determinants of diabetic nephropathy. It is conducted in eight U.S. clinical centers and a coordinating center, and with four ethnic groups (European Americans, African Americans, Mexican Americans, and American Indians). Two strategies are used to localize susceptibility genes: a family-based linkage study and a case-control study using mapping by admixture linkage disequilibrium (MALD).
  
  
  METHODS
  In the family-based study, probands with diabetic nephropathy are recruited with their parents and selected siblings. Linkage analyses will be conducted to identify chromosomal regions containing genes that influence the development of diabetic nephropathy or related quantitative traits such as serum creatinine concentration, urinary albumin excretion, and plasma glucose concentrations. Regions showing evidence of linkage will be examined further with both genetic linkage and association studies to identify genes that influence diabetic nephropathy or related traits. Two types of MALD studies are being done. One is a case-control study of unrelated individuals of Mexican American heritage in which both cases and controls have diabetes, but only the case has nephropathy. The other is a case-control study of African American patients with nephropathy (cases) and their spouses (controls) unaffected by diabetes and nephropathy; offspring are genotyped when available to provide haplotype data.
  
  
  CONCLUSIONS
  Identification of genes that influence susceptibility to diabetic nephropathy will lead to a better understanding of how nephropathy develops. This should eventually lead to improved treatment and prevention.
authors.affiliation: Diabetes and Arthritis Epidemiology Section, National Institute of Diabetes and Digestive and Kidney Diseases, Phoenix, AZ, USA.
authors.forename: William C
authors.initials: WC
authors.lastname: Knowler
authors.forename: Josef
authors.initials: J
authors.lastname: Coresh
authors.forename: Robert C
authors.initials: RC
authors.lastname: Elston
authors.forename: Barry I
authors.initials: BI
authors.lastname: Freedman
authors.forename: Sudha K
authors.initials: SK
authors.lastname: Iyengar
authors.forename: Paul L
authors.initials: PL
authors.lastname: Kimmel
authors.forename: Jane M
authors.initials: JM
authors.lastname: Olson
authors.forename: Rosemarie
authors.initials: R
authors.lastname: Plaetke
authors.forename: John R
authors.initials: JR
authors.lastname: Sedor
authors.forename: Michael F
authors.initials: MF
authors.lastname: Seldin
mesh_terms: D016022:Case-Control Studies; D003928:Diabetic Nephropathies / Q000208:ethnology* / Q000209:etiology / Q000235:genetics*; D005192:Family Health; D020022:Genetic Predisposition to Disease; D006801:Humans; D015810:Linkage Disequilibrium; D015337:Multicenter Studies as Topic / Q000379:methods*