We report the results of our analysis of the Genetic Analysis Workshop 12 simulated data set. Focusing on the isolated populations, we compare the efficiency of a new method, the maximum identity length contrast statistic (MILC) with the maximum likelihood score (MLS) in a genome screen strategy. MILC is a method based on the contrast of haplotype identity between transmitted and nontransmitted haplotypes in trios. It uses information on linkage and association. We found that MILC allows the detection of a risk factor corresponding to candidate gene 1 where the MLS fails, though the same population replicates were used. Interestingly, the association between this risk factor and the disease could not have been detected with the TDT at a genome-wide level.