Asthma gene discovered unique to raising risk in African-Americans
African-American asthma gene may explain rising rates
A new report highlights asthma risk in various groups that has implications for understanding how the disease develops beyond environmental and other contributors. In the genome wide study, one gene variant has been uncovered, unique to African-Americans, called PYHIN1.
The scientists say the finding might explain why asthma rates, which are on the rise in all groups, have been highest in African-Americans.
The findings come from the newly created EVE consortium and are published in the journal Nature Genetics. In the study, researchers also confirmed four genes associated with asthma risk in other populations that were previously discovered, in addition to the single gene variant for asthma risk in African-Americans.
Susan B. Shurin, M.D., acting director of the National Heart, Lung, and Blood Institute (NHLBI) of the National Institutes of Health, said, “Understanding these genetic links is an important first step towards our goal of relieving the increased burden of asthma in this population.”
Four other genes, discovered previously, combined with the new finding, add to valuable information about asthma risk in specific populations. The researchers did not find the PYH1N1 gene polymorphism in European-Americans.
The 17q21 locus and IL1RL1, TSLP, and IL33 genes were previously discovered to be present in over 40,000asthma cases in European populations, according to research published last year in the New England Journal of Medicine and again confirmed in the current EVE consortium meta-analysis.
According to Carole Ober, PhD, co-chair of the EVE Consortium, senior author of the study, and Blum-Riese Professor of human genetics and obstetrics/gynecology at the University of Chicago, …”it's important to understand whether these are caused by environmental exposures or by differences in genetic risk factors”, explaining, "We were able to show that almost all of the genes other than PYHIN1 are trans-ethnic and important in all of the groups."
Nine groups of investigators worked together to discover the gene variant that heightens asthma risk for African-Americans. Ober says geneticists now have five distinct gene variations that place ethnic groups at higher risk for asthma. The PYH1N1 gene variation is the only asthma gene found to be specific to African Americans. The authors say understanding genetic factors that contribute to asthma is a step forward for relieving global burden of the disease.
Nature Genetics (2011): doi:10.1038/ng.888
Meta-analysis of genome-wide association studies of asthma in ethnically diverse North American populations
Dara G Torgerson et al.; July 31, 2011
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