Historically, underserved minority populations have been the last to benefit from medical advances. Innovations from the Human Genome Project offer an opportunity to reduce health disparities by using targeted preventive programs and improving physicians’ awareness of common polygenic conditions and less common single-gene disorders that are more prevalent among several minority populations, such as persons of Mexican or African ancestry. The recent debate on race, ethnicity, and genetics includes a spectrum of opinion, from persons advocating a genetic explanation for health differences1 to others who suggest that such differences have much more to do with socioeconomic status and that pursuing the former merely increases discrimination.2 Such discussion is important, but meanwhile, family physicians face the reality of the increased exposure to genetic screening and the need for better documentation of familial predisposition for disease.3 It is vital that genomic medicine is not only used by more affluent members of society, but also reaches underserved minority populations.
Appropriate caution is needed. As described by Wattendorf and Hadley4 in this issue of American Family Physician, an individual’s ethnic or racial origin may trigger screening for specific inherited predispositions or single-gene disorders, such as sickle cell disease in persons of African ancestry.4,5 Preconceptional and prenatal genetic screening can inform couples of the risk that their child will be affected with these disorders.6 However, intermarriage and the uncertain ancestry of our increasingly diverse populations make genetic screening based solely on perceived ethnic origin problematic.7 In England, for example, an African-Caribbean woman with sickle cell trait (SCT) recently sued her doctor after her white partner was denied SCT testing, resulting in delayed diagnosis of their child with sickle cell disease. Subsequent confirmation of the diagnosis resulted in a breakdown of the couple’s relationship when the doctor stated that her partner could not be the baby’s father (B. Modell, written communication, 2004). This case exemplifies the importance of ascertaining ancestral genetic background rather than making assumptions based on perceived ethnic identity.
In the distant future, individual susceptibility to major common polygenic diseases such as heart disease and cancer may be ascertained from DNA genetic profiling. Until then, family physicians must rely on an accurate assessment of a patient’s family and ancestral history. Taking a conventional family history identifies genetic predispositions and environmental contributions, such as a high-fat diet and smoking. If we are also to record patients’ ancestry, a single question about ethnic origin appears inadequate but can be improved by collecting information about relatives’ ethnicity and country of origin.8 For example, the label “Latino” embraces many countries and cultures: in genetic terms, a Latino of Spanish-Caribbean origin may be at greater risk of SCT because of some African ancestry than a Latino of Mexican origin. The systematic collection of family information with sensitive exploration of ancestry and cultural background is likely to prove particularly useful in identifying diseases that cluster in certain families.4,9 This includes predicting adult onset of major chronic disease and identifying disorders with reproductive risk, which could trigger screening of other close relatives (“cascade screening”).5,10
Realizing the preventive benefits of identifying familial risk in underserved minority populations will demand greater attention to the inequalities in access to services and to achieving cultural competence in genomic health care delivery. Here, the dangers of failing to secure effective communication, including appropriate translation and interpretation, loom especially large. For example, discussion of genetic screening or inherited risk often involves presenting complex information with implications for the whole family. This interaction is a major challenge when the patient and physician do not share the same language and culture, and when counseling about inherited risk may directly affect a relative who is acting as an interpreter.11 Further, ethnic diversity in support and information networks, such as family involvement in a patient’s decision to have a genetic test, also may pose ethical dilemmas that are incongruous with traditional approaches to confidentiality.12,13 In all cases, caution is required to avoid stereotyping2,11 and to respond to each patient and their family individually, recognizing that community and sociocultural norms may not hold for them, and indeed may evolve over time.12,14
Advances in genomic medicine will offer an opportunity to narrow health disparities experienced by underserved minority populations through sensitive, targeted interventions. This goal does not require great technologic advances, but can be reached by improving the training of physicians in accurate, culturally competent family history taking.15