The Link Between Getting Mountain Sickness and Genetics

Discover how genetics may inform why you are not just a “beach person” or a “mountain person,” but actually how they may make you more prone to specific experiences like acute mountain sickness. 

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Have you ever dreamed of traversing new peaks in Nepal or hitting the ski slopes in Aspen? Or maybe vacationing to more mountainous lands but you’re worried about altitude sickness? 

You’re not alone. When you're ascending to higher ground, heights may not be the only thing to worry about, especially if it’s over 8,000 feet. More formally known as acute mountain sickness, altitude sickness affects thousands of people throughout the world each year. 

In extreme cases, acute mountain sickness can even lead to death.

Although it would be thought that anyone who ventures to new heights would feel a little bit light-headed and short of breath, the truth is that some people are more susceptible to acute mountain sickness than others, and the link is mostly genetic. 

Knowing if you’re at higher risk of experiencing acute mountain sickness can help you plan out your trip and allow you to understand your health profile better, leaving you to fully prepare for the mountainous roads ahead.

Let’s explore the link between acute mountain sickness and genetics together.

What is acute mountain sickness?

‍Every year, millions of people ascend to altitudes higher than 8,000 ft (2500m) above sea level  for travel, work, or military-related activities. 

Some people are susceptible to altitude sickness after rapidly changing from lower to higher altitudes. The syndrome is known as acute mountain sickness (AMS). 

Symptoms

Acute mountain sickness symptoms typically appear within hours of reaching a higher altitude.

Mild symptoms include:

• dizziness
• headache
• muscle cramps
• insomnia
• nausea or vomiting
• swelling in the hands, feet, or face
• rapid heart rate 
• shortness of breath 
• irritability
• loss of appetite

For those with more severe cases, symptoms may include:

• confusion
• cough
• chest congestion, or pain
• loss of balance

If you ever experience severe symptoms it is critical to call for immediate emergency medical assistance. 

Causes

The leading cause of AMS is lack of oxygen. 

As you ascend to higher altitudes, oxygen levels and air pressure both decrease. 

Everyone’s body acclimates differently to changes in the environment. However, your level of exertion also plays an important role in whether or not you develop AMS. 

Although the primary cause of AMS is believed to be a lack of oxygen, populations in highland regions, such as the Ethiopian Highlands, the Andes, and the Tibetan Plateau, have a much lower risk of suffering from any mountain illness. 

Interestingly, even under the same conditions, certain people accustomed to lower altitudes are still more susceptible to AMS than others. 

Therefore, it’s generally assumed that genetic background plays a pivotal role in the differences in susceptibility between lowlanders and highlanders.

The Role of Genetics in Acute Mountain Sickness

Genetics plays a pivotal role in your risk of acute mountain sickness when traveling to higher altitudes.

One of the susceptible genes to AMS is the vascular endothelial growth factor (VEGF) gene. 

VEGF plays an important role in regulating blood vessel cell generation, endothelial cell proliferation (maturing blood vessels), and capillary functions, which have been significantly affected by large changes in air pressure and oxygen availability.¹

A previous study suggested a possible relationship between VEGF and AMS.² However, the sample size was relatively small. 

Since most of the Chinese Han population resides in the lowland region, they may be an appropriate population for investigating the association between genetic factors and susceptibility or resistance to AMS.

To clarify the relationship between genetics and AMS in Han Chinese, 604 male participants traveled from Chengdu (500m above sea level) to Lhasa (3700m above sea level). Their demographic information was collected a week before travel, and AMS-related symptoms, including headache, dizziness/light-headedness, gastrointestinal symptoms, and fatigue, were noted 18–24 hours after arriving in Lhasa. 

In total, 23 SNPs were selected for further analysis. Results showed that 4 SNPs, including some along the VEGF gene,³ were associated with the risk of developing AMS even after adjusting for age, BMI, and smoking status. They also found that CT and TT genotypes were associated with increased AMS risk and AMS-related headaches compared to the CC genotype.⁴

The AMS-associated variants identified in this study have potential use in screening susceptible populations and predicting the clinical symptoms that lead to AMS, which will benefit soldiers and travelers who rapidly change altitudes.

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How do I determine if I am at increased risk of AMS?

DNA analysis is the best way to determine your genetic predisposition to acute mountain sickness and is especially important to know if you travel often for work, military duties, or pleasure. 

Knowing about your genetic code can help you protect your health and understand yourself better. But you can’t learn about your genetic makeup if you don’t upload your data for an in-depth analysis from Genomelink. Don’t take one more weekend trip to the mountains until you know what your Genomelink report says about altitude sickness.

A DNA testing kit is simple to use, and your genetic results can reveal many answers to the questions you may have about AMS and other genetically-linked health conditions. Don’t wait another day to understand your health better; Unlock your full genetic potential now. Once you’ve taken an at-home DNA test, you can use your raw DNA file to analyze your genetic profile further. 

Simply sign in to the Genomelink dashboard to upload your DNA file, and our experts will take care of the rest.

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