A family set method for estimating heredity and stress--II : Preliminary results of the genetic methodology in a pilot survey of Negro blood pressure, Detroit, 1966-1967

Abstract

A prior article described in detail a pilot survey designed to measure the effects of heredity and stress on blood pressures among Negroes residing in high and low stress census tracts in Detroit. This report outlines the construction of a genetic variable to analyze the heritable component in blood pressure variability using a family set composed of an index and spouse, a sibling and a first cousin of index, and an unrelated person in the tract matched to index. Given the theoretical proportions describing the degree to which genes are shared between siblings and first cousins, then it follows that variability of a given trait will increase predictably within each family set. Findings from a limited sample of 56 family sets indicate support for a genetic distance scale when measured against variables such as height and skin color; however, the relationship with blood pressure levels is inconclusive. A study now underway will more critically test the tentative findings from this pilot survey.