We report single-point and multipoint results from three statistical genetics software packages using a variance components approach for quantitative traits. When possible, we have shown the effects of covariates. Results from GENEHUNTER, SOLAR, and ACT software packages are compared for the quantitative trait immunoglobulin E (IgE) using chromosome 5 asthma familial data from Oxfordshire (England), Perth (Australia), and Freiburg (Germany), and using the genome-wide German data. Although few differences among variance components results for GENEHUNTER, SOLAR, and ACT were detected on a limited region of chromosome 5, these packages showed larger disagreement in the German data for chromosomes 1, 9, and 14.