Family-based association tests (FBAT) (Rabinowitz and Laird, 2000) was used for genetic association analyses of alcohol dependence diagnosis. FBAT builds also on the original transmission disequilibrium test (TDT) method (Spielman and Ewens, 1996) in which alleles transmitted to affected offspring are compared with the expected distribution of alleles among offspring. The approach compares the genotype distribution observed in the “cases” to its expected distribution under the null hypothesis; in this case, the null hypothesis tested was “no linkage and no association” (Lange and Laird, 2002).
