Patent ID: 7124033

Claim:
A method for identifying matched groups prior to performing a study, the method comprising: prior to performing a study, identifying members of a control group and members of a case group; for each of a number of selected genetic markers, genotyping a plurality of members in the control group and a plurality of members in the case group, wherein the genotyping identities a set of alleles corresponding to the genetic markers for each member of the pluralities, and wherein the genetic markers are selected to identify differences in population structure between members; and determining if the groups are matched based on the genotypes of said case group and said control group by (i) determining observed chi-squared score statistics of association with a phenotype based on counts of each genetic marker allele among members of the case and control groups; (ii) comparing a distribution of the observed chi-squared score statistics with an expected chi-squared score statistics distribution in a Q—Q plot; and (iii) determining if the differences between the observed and expected statistics distributions exceed an acceptable range, wherein if the differences between the observed and expected statistics distributions do not exceed an acceptable range the groups are determined to be matched.