Family resemblances in height and relative weight in the Framingham Heart Study.

The correlations of both height and relative weight (the Quetelet Index: wt/ht2) were studied amongst adult relatives in the Framingham Heart Study. The parental generation was first examined starting in 1949 when they were aged 30-62 years. The offspring (and their spouses) were examined beginning in 1971 when they were aged 20-49 years. Thus, it was possible to compare adult levels of body size in two generations. For height there are correlations between relatives that suggest large genetic variation for adult body height. For relative weight as measured by Quetelet's Index, the associations between relatives show a pattern that is more difficult to interpret and gives little support for sizable contributions of genetic differences to the population variation in relative weight. Although there is little evidence for large genetic variation for obesity, there is marked resemblance for obesity among first-degree relatives. This fact may be used to advance the family-based approach to screening, identification and intervention on the cardiovascular complications of obesity.