Design.
—Survey of a random stratified sample of the US population.

Participants.
—Male and female children aged 13 years or younger (mean, 5.3 years; SD, 3.7 years; median, 4.0 years; range, 6 months to 13 years) were chosen from National Health and Nutrition Examination Survey II data.

Interventions.
—None.

Measurements/Main Results.
—Using multivariate commingling analysis, we evaluated the hypothesis that a major gene produces a syndrome involving the phenotypic indicators of body mass index (in kilograms per square meter), subscapular-to-triceps skinfold thickness ratio, systolic blood pressure, and diastolic blood pressure. Maximum likelihood estimation was used to test competing models. A model with three component distributions and unequal variance-covariance matrices fit significantly better than any competing model.

Conclusions.
—Our findings support the existence of a distinct cardiovascular disease risk syndrome in children and suggest that it may be the result of a major gene with pleiotropic effects.

(AJDC. 1993;147:1298-1302)