doi:10.1038/nindia.2015.65 Published online 18 May 2015
Researchers have identified genetic markers associated with mountain sickness. New research says people experiencing the sickness might be genetically predisposed, due to aberrations in the alleles that maintain oxygen homeostasis in the body1.
Under normal conditions, a cell-to-cell communication pathway called apelin system, and the peptide apelin, maintain the oxygen balance in body. Apelin triggers the production of nitric oxide (NO), a blood vessel dilating gas, for more oxygen availability.
People experiencing shortness of breath, and other breathing-related acute illnesses, called high altitude pulmonary edema (HAPE) at high altitudes showed methylation of alleles that trigger the apelin and NO production, compared to normal people. Because of this aberration, the genetic switch called hypoxia inducible factor (HIF) cannot switch on the apelin producing alleles, resulting in HAPE in the predisposed individuals.
“There are still unresolved queries, which need to be addressed”, says Aastha Mishra, the lead author of the study. Though there is already a drug called sildenafil that helps predisposed people in producing NO at high altitudes, the researchers hope that their work would bring better therapeutic strategies and interventions.
1. Mishra A., et. al. Genetic differences and aberrant methylation in the apelin system predict the risk of high-altitude pulmonary edema. P. Natl. Acad. Sci. 2015 112 (19) 6134-6139. doi: 10.1073/pnas.1422759112