Geneticists at North Carolina State University have revealed an interesting lesson in gene expression: where you live can have significant impact on how your genes are expressed.
The scientists focused on a sample of 46 Moroccan Amazighs, a relatively homogenous group genetically-speaking. The subjects included desert nomads, mountain agrarians and coastal urban residents. The researchers analyzed the white blood cells of the group “to study the impact of the transition from traditional to urbanized lifestyles on the human immune system.” The results surprised even the scientists themselves: gene expression in the group varied by up to one-third based on geographic location and corresponding lifestyle.
They used the latest tools for characterizing the sequence and expression of all 23,000 human genes to compare the three Moroccan Amazigh groups. These groups were chosen because they have a similar genetic makeup but lead distinct ways of life and occupy different geographic domains. Thus, differences in gene expression profiles between the three groups would likely be due to environmental and not genetic factors. The team uncovered specific genes and pathways that are affected by lifestyle and geography. For example, they found respiratory genes were upregulated, or turned on, more frequently in the urban population than in the nomadic or agrarian populations.
To confirm that differences were environmentally related, the scientists reviewed the genetic profile of random subjects in the three groups and found very little genetic variance. As they had expected, the significant difference in gene expression was initiated by environmental factors.
The differences they found in genetic expression logically fit with the environments’ corresponding challenges. The urban dwellers dealt with the city’s manufacturing-associated air pollution and higher level of viral pathogens on a daily basis. The upregulation observed in their respiratory genes, the scientists submit, is a response to the compromises present in their urban environment. And pollution was only one piece of the environmental picture and the impact of modern urban living. According to the scientists, the striking differences in gene expression were the likely result of a “combination” of lifestyle factors, including “nutrition, history of immune exposure, and psychological stress.”
This study, along with other research that examines the impact of environment on gene expression, affirms the message we try to offer on a regular basis: we are not at the mercy of our genes. How we play our genetic hand can matter as much as the cards we hold. Where we live, what we eat, what we’re exposed to and how we’re medically cared for, how active we are, and what levels of stress we deal with influence the expression of our genes. In keeping with this principle, the scientists who conducted the study offer this recommendation for future medical research and care:
Insight gained from this study highlights the impact transitions from traditional to modern lifestyles likely have on human disease susceptibility and further warrant the need to incorporate gene expression profiling alongside genetic association studies for the prediction of disease susceptibility.
Our modern lifestyles, as we say in the Primal Blueprint, create a deep chasm between our genetic expression and that of our ancestors. This study of populations in Morocco gives us a hint of that gap. It’s no coincidence that the Blueprint incorporates diet and physical activity similar to that of our primal history. (With good old Grok as our distinguished guide.) Likewise, the Primal Blueprint includes understanding and mitigating the damage created by the compromises of modern circumstance. Our bodies are remarkably adaptable, and genetic expression is evidence of this. However, this adaptability, constantly challenged and finally overstrained, cannot by itself compensate for the many modern burdens we impose. Our day to day choices matter, and knowledge is key. Thoughts? Check back for more along the lines of lifestyle choices and gene expression in the future.