Racial Differences in Allergy Rates: Genes or Environment?

Posted by Diane Tober March 21, 2013
Biopolitical Times
A recent study at Henry Ford Hospital in Detroit found that African-American children are three times as likely as Caucasian children to be sensitive to at least one food allergen, and concluded that this is due to “race and possibly genetics.” In a ScienceDaily press release, lead investigator Dr. Haejim Kim said,
Our findings suggest that African Americans may have a gene making them more susceptible to food allergen sensitization or the sensitization is just more prevalent in African American children than white children at age 2 [emphasis added].
The study was conducted by giving kids skin tests for sensitivity to food and environmental allergens. As described in the press release, it involved no genetic testing at all, and did not control for variables such as environment or socio-economic differences. Yet Dr. Kim was willing to speculate that the racial disparities between allergy rates observed by her team are related to racial genetic differences.

Kim went on to note that more research is needed to determine if African Americans “have a [susceptibility] gene” or not. But predictably, her ambiguous comment unleashed misleading media coverage that turned a speculative remark into the definitive conclusion that racial disparities in children’s allergy rates are due to genes that vary by race. Some examples:
[Headline] Childhood Food Allergies Linked to Race and Genetics: Recent research revealed childhood food allergies could be linked to race and genetics rather than environmental allergies.

[Headline and lead] Why are black children developing food allergies at a dramatically faster rate? Childhood food allergies are linked to your race rather than to the environment, a new study…reports.

[Headline and lead] Could Race Be Behind Childhood Food Allergies? New research suggests that race and genetics do play a role in children’s sensitivity to developing certain allergies.
What explains the appeal of this kind “gene fetishism” and of linking it to race? It’s certainly not any overwhelming scientific evidence.

One body of research has focused on environmental factors in allergy. A study published in Clinical Pediatrics, for example, found that peanut allergies are twice as prevalent in urban centers as in rural communities, and hypothesized that the high level of pollutants found in urban areas may contribute to the development of the allergies. Other studies support the so-called “hygiene hypothesis” – the idea that living in a cleaner environment may make people's immune systems more sensitive, and increase the prevalence of allergies.

In short, the jury is still out on the causes of food and environmental allergies. What we can say with some degree of confidence is that popular news outlets too often depict inconclusive research as fact, and that this tendency seems particularly strong when the topic is related to race and genetics.