Celiac disease (CD) is a chronic intolerance to gluten, the protein found in wheat, barley, and rye. When gluten enters the digestive tract of someone with CD, it triggers an autoimmune attack, and the resulting inflammation destroys the villi of the intestines. Without these finger-like projections of the intestinal surface, normal nutrient absorption can’t take place and serious digestive symptoms result.
Nearly every article about celiac disease states that the condition is most frequent in people of Northern European descent. Despite this consensus, I was hard-pressed to find a chart or set of statistics that directly compare the prevalence by racial groups, so the above graph is the best I could find. It at least shows that the rate of celiac disease in African, Hispanic, and Asian-Americans is lower than the rate of the general population, which factors in Caucasian Americans.
One of the highest risk factors for celiac disease (CD) is a family history of the condition. Nearly every patient diagnosed with CD has a specific form of the HLA genotype that is associated with causing the disease in conjunction with environmental factors. Since the main gene pool of people with this mutation originated in Northern Europe, all of their descendents throughout North America, Australia, South Africa, etc. are at a higher risk for inheriting this genetic predisposition to the disease.
The medical community agrees that celiac disease is generally underdiagnosed, Another possible reason minorities have a lower prevalence of CD is that in some communities, they are less likely to have access to health care, and are less likely to undergo the intestinal biopsy that leads to a CD diagnosis. Because of this, reported diagnoses of CD in minorities might not fully represent the true number of cases. The processing of wheat and bread are also linked to the incidence of celiac disease, which has multiplied by four times in the past 50 years. Certain ethnicities may not include as many wheat products in their diet as Caucasians, leading to a lower incidence of gluten intolerance.
This week’s materials helped me separate the concepts of race and genetics. I learned that race is a socially-constructed idea that can only be determined by self-identification. Scientists agree that race has no genetic basis. This means that no genetic test or biological examination could distinguish one race from another.
Genetics, on the other hand, is comprised of the concrete structures of DNA that impact how the body functions. Specific genotypes can be linked to disease, either as a direct cause of some malfunction, or as a risk factor that can predispose someone to developing a disease.
The line between genetics and race can sometimes be blurred when studying their impact on health. For example, in the Pima Indians in the U.S. have a severely high incidence of Type II diabetes. This is due to a specific gene preserved in their population because it once gave them a survival advantage to store energy during famines. However, the gene has been limited to their specific ethnic group since for the most part it has not been passed on to generations outside of the Pima population.
http://news.medill.northwestern.edu/chicago/news.aspx?id=150813 (for information and graph)