First, conclusions about the contribution of genetics should be based on direct tests of genetic traits. Since an individual’s race is of very limited use as an indicator of genetic traits, directly measuring the relevant gene is the reliable method for assessing genetic risk.123, 125, 140 The underlying biological mechanisms of disease sometimes vary across race141 and differential treatment effectiveness is sometimes found across racial groups.142 Residual racial differences in biological processes after SES is adjusted for, are often interpreted as due to innate genetic differences.123 However, racial differences in observed biological factors do not necessarily reflect racial variation in genotype. Given the marked differences in environmental conditions noted earlier, they could also reflect differences in unmeasured environmental factors, gene expression, and other biological adaptations to the environment, or some combination of these factors. Researchers should also pay attention to variation within race, as well as, differences across racial groups. For example, a meta-analysis of 15 clinical trials found that blacks and white patients differ in their responses to antihypertensive medications with white patients responding better to beta blockers and
