Genetic and Environmental Influences on Gas Exchange

Abstract

Gas exchange is a critical process required for sufficient tissue perfusion. The environment, genetics, or a combination of the two can affect this process. Various strategies have evolved to overcome the specific gas exchange challenges in different environments and it is clear that some genes are pivotal to the development of gas exchanging organs (e.g. Bmp4). Lower partial pressure of oxygen (hypoxia), reducing the partial pressure gradient, makes gas exchange more challenging and therefore the height to which gas exchangers can travel above sea level is limited. However, some human populations (e.g. Tibetans) and other animals (e.g. Bar-headed goose) have adapted well to profoundly hypoxic conditions, suggesting genetic factors are important. Gas exchange can also be affected by air pollution, including particulate matter and ozone among others, and exposure can lead to cardiopulmonary responses depending on individual susceptibility or preexisting disease, both of which have genetic and environmental components. Diseases that affect gas exchange include, but are not limited to, pulmonary hypertension, chronic obstructive pulmonary disease (COPD), and bronchopulmonary dysplasia. Moreover, different species successfully exchange gases in their specific environment, for example animals that fly or burrow. Under these conditions, common genetic mechanisms, and their interaction with environment, help to maintain, or are detrimental to, gas exchange.

Blood pressure levels among Indigenous children living at different altitudes

“…A previous study performed among Turkish children aged 10 years showed that children living at high altitude (1,725 m) had higher systolic and diastolic BP levels compared with children from similar ethnic backgrounds who lived at sea level (Arslan et al 2003). Similar findings have been reported in children from Pakistan, with a prevalence of hypertension of 12.2% (Jafar et al 2005).…”

“…Furthermore, the decrease of partial pressure gradients hinders the exchange of gas, causing chronic insufficiency of oxygenated blood circulation (Zheng et al 2012). This results in the decrease in the blood being supplied to the kidneys and the consequent release of renin (Howden et al 2012). This process increases the vasoconstriction of arteries (Howden et al 2012).…”

“…This results in the decrease in the blood being supplied to the kidneys and the consequent release of renin (Howden et al 2012). This process increases the vasoconstriction of arteries (Howden et al 2012). Therefore, cold climate, chronic hypoxia, and elevated hemoglobin levels due to high altitude could have an influence on BP among indigenous children living in SAC.…”

Relationship between altitude and the prevalence of hypertension in Tibet: a systematic review

“…This causes a drop in blood supply to the kidneys, and the subsequent release of renin that contributes to the vasoconstriction of the arteries. 49 …”

Reply to “Discussion of ‘Blood pressure levels among Indigenous children living at different altitudes’”

“…Furthermore, we included a paragraph in the discussion section describing studies from other authors that postulate that the decrease of partial pressure gradients hinders the exchange of gas, causing chronic insufficiency of oxygenated blood circulation (Zheng et al 2012). This causes a drop-in blood supply to the kidneys and the subsequent release of renin, which contributes to the vasoconstriction of arteries (Howden and Kleeberger 2012), suggesting that decreased saturation could contribute to hypertension. However, we believe that our study has added something valuable to the literature.…”