661vasodilators is more effective in treating heart failure in black persons than in white
persons and that ACE inhibitors have little effi cacy in blacks.
In order to address the health concerns of blacks in the US, Howard University
(Washington, DC), a historically black institution, started to create the nation’s larg-
est repository of DNA from African-Americans in 2003. The samples were used to
fi nd genes involved in diseases with particularly high rates among blacks, e.g.
hypertension and diabetes. Over a 5-year period, blood samples or cheek swabs
were gathered from 25,000 persons, mainly patients at hospitals associated with the
Howard College of Medicine. The genetic information would help to fi nd the cause
of a disease, predict susceptibility to an illness and help to choose a drug that would
work best for a particular patient.
Race is frequently used by clinicians to make inferences about an individual’s
ancestry and to predict whether an individual carries specifi c genetic risk factors
that infl uence health. The extent to which race is useful for making such predictions
depends on how well race corresponds with genetic inferences of ancestry. Recent
studies of human genetic variation show that while genetic ancestry is highly cor-
related with geographic ancestry, its correlation with race is modest. Because of
substantial variation within human populations, it is certain that labels such as race
will often be an inaccurate proxy when making decisions about disease predisposi-
tion and drug response. Because data on the correspondence of race, ancestry, and
health-related traits are limited, particularly in minority populations, geographic
ancestry and explicit genetic information are alternatives to race that appear to be
more accurate predictors of genetic risk factors that infl uence health and should be
considered in providing more personalized health care.
However, the public health relevance of various studies remains controversial.
Many researchers and policy makers argue against the use of racial or ethnic catego-
ries in medicine, saying that classifying people according to race and ethnicity rein-
forces existing social divisions in society or leads to discriminatory practices. Race
has not been shown to provide a useful categorization of genetic information about
the response to drugs, diagnosis, or causes of disease. The current concept of race is
a social construct defi ned by geography and culture with no genetic basis. There are
no genetic variants that are found in every member of one race and none of another.
Risk factors associated with race are not exclusive and may be found in several
different races. There are biological variations among people but they may not par-
allel the categories of races as practiced now.
There are racial and ethnic differences in the causes, expression, and prevalence
of various diseases. The relative importance of bias, culture, socioeconomic status,
access to care, and environmental and genetic infl uences on the development of
disease is an empirical question that, in most cases, remains unanswered. Never-the-
less ignoring racial and ethnic differences in medicine and biomedical research will
not make them disappear. Rather than ignoring these differences, scientists should
continue to use them as starting points for further research. Only by focusing
attention on these issues can we hope to understand better the variations among
racial and ethnic groups in the prevalence and severity of diseases and in responses
to treatment.
Race and Personalized Medicine