The method of association arrays is applied to plasma total cholesterol, triglyceride, and high density lipoprotein cholesterol concentrations measured for 2485 young men and women aged 17-18 years and living in Jerusalem, and for their parents. These triad families are divided into five groups according to whether they were of mixed "origins." Stronger associations are present for all lipid and lipoprotein cholesterol variables in Asian and African families relative to families of other origins, possibly reflecting the more disciplined life-style patterns in these families relative to other families. Parent and offspring values exhibit positive association for all lipid variables in all groups. Patterns of familial similarity revealed by the association arrays are discussed in relation to historic and cultural differences among groups.