Common haplotypes in the beta-2 adrenergic receptor gene are not associated with acute mountain sickness susceptibility in Nepalese.

Acute Mountain Sickness (AMS), the most common and least serious of the altitude-related illnesses, is frequently experienced by sojourners traveling above 2500 m. Although altitude and rate of ascent are likely the most critical factors in determining whether the condition will develop in a person, interindividual variation and patterns of susceptibility suggest that there may be genetic risk factors as well. We hypothesized that variants in the gene that encodes the beta-2 adrenergic receptor (the principal catecholamine receptor in the lungs) are involved in the etiology of AMS and tested this hypothesis in cohorts of Nepalese individuals who developed or did not develop AMS when attending the Purnima Festival at Lake Gosain Kunda at 4380. Polymorphisms that could serve as markers for the common haplotypes encompassing the gene were chosen using the HapMap database. We found no association between any alleles at the seven highly informative polymorphic loci (tagSNPs) that we assayed and AMS status, suggesting that variants in, or near, the beta-2 adrenergic receptor gene do not contribute to AMS susceptibility in this population. This study is the first application of the HapMap database and associated haplotype mapping tools to the understanding of altitude-related pathologies.