Evidence of linkage to loci for both asthma and allergic rhinitis on chromosome 12q 14.3-q24.1

ABSTRACT

As many as 80 percent of asthmatics have atopy and between 60 and 80 percent of allergic asthmatic have coexisting rhinitis. It has been proposed that asthma and allergic rhinitis are essentially the same inflammatory disease of human airways. Previously, we provided the first evidence for linkage of asthma and "high" total serum IgE concentration to chromosome 12q markers among families from Barbados and the US. To identify loci in this chromosome 12q region contributing to the distinct clinical phenotypes of asthma and allergic rhinitis, we conducted linkage analyses among 33 multiplex Barbadian families using densely-spaced microsatellite markers in the 12q14.3-q24.1 region. Maximal evidence for linkage to asthma and allergic rhinitis occurred at markers separated by 4.5 cM. D12S326 and D12S1052 = (NPL = 3.52, p = 0.001 and 1.72, p = 0.039, respectively), these two markers lie 9.13 cM downstream from IFNG. There was no evidence of linkage to either phenotype at markers flanking STAT6. These results suggest that a common gene on the long arm of chromosome 12 is important for both asthma and allergic rhinitis.(AU)