Genetic and environmental determinants of growth of school-aged children in a rural Colombian population

Abstract

Parent-offspring correlations and heritabilities of body measurements from midparent-offspring regressions are presented for school-aged children from the village of Tenza, Colombia (N = 403 families). Parent-child correlations and midparent regressions in this subsistence farming sample are similar in magnitude to those for well nourished, urban industrial samples, suggesting that the environmental component of variability in body size is the same regardless of the environment. Tenza children are significantly shorter and lighter than upper class Bogota children, and Tenza parents have mean heights and weights similar to those of other lower class Colombian samples. Chronic undernutrition has apparently affected the growth of parents and continues to affect the growth of the present generation. Although it has been hypothesized that heritability of growth might be reduced in samples experiencing malnutrition and its sequelae, such a reduction may only be observable where environment of parents during their development is different from that of their offspring, which is not the case here. The pattern of heritabilities with respect to different body measurements in Tenza is similar to that seen in well nourished samples, except that measurements of breadth (biacromial, bicristal, bicondylar) have heritabilities similar in magnitude to those of linear measurements (height, sitting-height, subischial length) especially in males; heritabilities of some measurements related to adiposity are significantly higher in daughters than in sons.