title: [Case-parental control study].
abstract: OBJECTIVE
  To introduce the methodology on the design and statistical method as well as analysis of published data related to case-parental control study.
  
  
  METHODS
  Data from a research on association between the human neural tube defects and the T allelic variant TIVS7-2 was analyzed by haplotype relative risk (HRR), genotype relative risk (GRR) and transmission/disequilibrium test (TDT) methods.
  
  
  RESULTS
  Using the HRR method, HRR value was 1.33 (chi-square statistic is 1.4618 with P = 0.2266). The results of the GRR method showed that psi(1) value was 1.26 and psi(2) value was 0.98 (chi-square statistic is 3.1809 with 2 df, P = 0.2038). The transmission/disequilibrium test showed that TDT was 1.4516 with P = 0.2283. All results suggested that when a weak association of TIVS7-2 allele with neural tube defects was found, there was no evidence showing the statistical difference.
  
  
  CONCLUSIONS
  The case-parental control design method avoids population stratification when parents used as controls. This method might be used to test the association between genes and disease, as well as to evaluate the gene environmental interaction.
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
mesh_terms: D016022:Case-Control Studies; D004247:DNA / Q000235:genetics; D004812:Epidemiologic Methods; D005192:Family Health; D005260:Female; D005819:Genetic Markers; D005838:Genotype; D006801:Humans; D008297:Male; D010290:Parents
chemical_list: D005819:Genetic Markers; D004247:DNA