Complete multipoint analysis as implemented by MAPMAKER/SIBS was used to identify the chromosomal regions with the strongest evidence of linkage. Three different quantitative sib-pair methods were compared. For each trait the maximum lod/Z score was used to implicate a chromosomal region. For trait Q5, chromosome 5, the analysis was repeated in a second data set to test for replication of the result from the first data set. The initial screen was carried out using complete parental information and the first sibling pair from each nuclear family. The effect of removing the parental genotypes and the use of multiple independent sibs was examined in the second data set for Q5, chromosome 5.