FAMILY RESEMBLANCE IN CARDIORESPIRATORY TRAITS

Family aggregation of cardio-respiratory traits in the population of M iddle Dalmatian islands has been investigated on a random sample of ad ults. The similarity between first-degree relatives has been quantifie d by calculating Pearsons >>product-moment<< co-efficient of correlati on. The obtained results have been compared with the corresponding res ults of other authors, and discussed with respect to the possible infl uence of genetic and ecological factors on their formation. The highes t correlation values within a family have been found in lung function parameters, whereas the lowest correlations have been found for restin g pulse rate, and maximum oxygen uptake values. Exceptionally high cor relations for lung function parameters among brothers and higher fathe r-offspring correlations for those traits compared with other physiolo gical traits, speak in favor of strong common family environmental inf luence on lung function traits, acting especially among male family me mbers. The pattern of family correlations for systolic blood pressure resulting in a lesser resemblance in males and in intergenerational pa irs, suggests either different environmental influence, either differe nt sensibility - higher in males -to those influence. In contrast, the pattern of family correlations found for diastolic blood pressure, su ggests that influences - whether they are primarily genetic or environ mental - act on all family members with the same degree.