HLA-G: an asthma gene on chromosome 6p.

We identified HLA-G as an asthma susceptibility gene in multiple populations and demonstrated that variation in this gene influences subsequent risk for asthma. Prenatal exposure to factors that are correlated with maternal BHR (or perhaps BHR itself) interacts with fetal genotype to determine risk, however. Among fetuses of unaffected mothers, the +1489TT genotype is a marker for increased risk, whereas among fetuses of affected mothers the +1489CC genotype is a marker for increased risk. Studies are underway to understand the mechanism for this interaction and the role of this gene in the pathogenesis of asthma.