US researchers have discovered a genetic mutation unique to African-Americans that could help explain why blacks are so susceptible to asthma.
Earlier studies looking for asthma genes have turned up several, but most of the studies have been too small to confirm these genes or to detect genetic changes unique to different races.
The new study, published yesterday in the journal Nature Genetics, pools research from nine groups looking for genes associated with asthma among ethnically diverse North American populations. It confirmed four genes that had been seen in previous studies and a fifth that showed up only in people of African descent.
“This is the first discovery of a gene where we see a signal in African-Americans only,” Dan Nicolae of the University of Chicago, a study author and co-chair of a national research consortium that identified the gene, said in a phone interview.
“The rates of asthma in different ethnic groups are different. African-Americans have shown increasing asthma rates. We don’t know why, it can be due to changing environmental risk factors,” Mr Nicolae said. The new findings, he added, suggested genetics also played a significant role.
Dr Susan Shurin, acting director of the National Heart, Lung and Blood Institute, said: “Understanding these genetic links is an important first step towards . . . relieving the increased burden of asthma in this population.”
