NEW YORK (GenomeWeb News) – Johns Hopkins University researchers plan to run a study that will sequence the genomes of 1,000 people in search of genetic causes for the disproportionate incidence rates of asthma among people of African descent, the school announced today.
Funded by a $9.5 million grant from the National Heart, Lung, and Blood Institute, the researchers will sequence and study the genomes of 500 asthmatics and 500 non-asthmatics in search of genetic markers that may help explain why as many as 20 percent of African-Americans have asthma.
The Johns Hopkins researchers have contracted Illumina to create a commercially available microarray test that will be used to find genetic variants. Illumina and Affymetrix both have already created similar genotyping chips, but they were both developed from whole genome sequencing projects involving mainly Europeans. This effort aims to fill in the picture with genetic information from Africans.
“One of our biggest barriers as researchers trying to find the underlying genetic roots of disease in minority groups has been the persistent lack of microarray testing tools relevant to each racial profile, especially African-Americans,” Kathleen Barnes, director of Johns Hopkins' Genetics Research Facility and the Lowe Family Genomics Core Laboratory, said in a statement.
"Asthma is exacerbated by social factors, such as poverty, and inadequate education and access to medical care," she added, "so separating out the genetic component is particularly complex, but scientifically doable."
Barnes and her colleagues plan to sequence the genomes of people of African descent who have been selected from an international group of participants in existing genetic studies. Those having their genome sequenced have either already been clinically diagnosed with asthma or without, or have other kinds of compromised lung function. Their family histories will also be well-documented.
The participants in the project will be chosen from 15 academic research centers from around the US, the Caribbean, and South America, and from four research sites in Western Africa.
Barnes, who is principal investigator on the project, and her research team will make their findings available via the dbGAP national database of genome-wide association studies at the National Library of Medicine.
According to Johns Hopkins, an estimated 20 million Americans have asthma. The disease accounts for 25 percent of trips to emergency rooms for breathing problems, and is the most chronic condition among children.