title: [Introduction on "case-sibling control design"].
abstract: OBJECTIVE
  To introduce the design and statistical methods of case-sibling control design and to analyze the published data.
  
  
  METHODS
  Data from an association study between the coronary heart disease and methylenetetrahydrofolate reductase gene C677T polymorphism was analyzed by the sib transmission/disequibrium test (s-TDT) and the sibship disequilibrium (SDT) methods.
  
  
  RESULTS
  Using s-TDT method, Z value was 0.27 with P > 0.05. The result of SDT method showed that chi-square was 0.31 with 1 df, P > 0.05. All results suggested that neither s-TDT nor SDT showed significant difference between the transmitted and untransmitted methylenetetrahydrofolate reductase gene C677T allele distributions.
  
  
  CONCLUSIONS
  Case-sibling control design might avoid population stratification by using siblings as controls thus might be used to test association and linkage between genes and disease.
authors.affiliation: Department of Epidemiology and Biostatistics, School of Public Health, Nanjing Medical University, Nanjing 210029, China.
authors.forename: Hong-gang
authors.initials: HG
authors.lastname: Yi
authors.forename: Feng
authors.initials: F
authors.lastname: Chen
authors.forename: Hao
authors.initials: H
authors.lastname: Yu
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhao
authors.forename: Dong-hua
authors.initials: DH
authors.lastname: Lou
mesh_terms: D016022:Case-Control Studies; D016009:Chi-Square Distribution; D003327:Coronary Disease / Q000235:genetics; D004812:Epidemiologic Methods; D005787:Gene Frequency; D056726:Genetic Association Studies; D008040:Genetic Linkage; D006801:Humans; D042965:Methylenetetrahydrofolate Reductase (NADPH2) / Q000235:genetics; D011110:Polymorphism, Genetic; D012107:Research Design; D035781:Siblings
chemical_list: D042965:Methylenetetrahydrofolate Reductase (NADPH2)