Some people naturally seem to attract mosquito bites, while others go untouched. Several factors can make you an enticing meal for a mosquito, including human genetics. While your DNA appears to play a small role, the presence of specific genetic markers can still be linked to whether your smell is attractive to mosquitoes.

Whether mosquitoes tend to fancy you or if they’re more likely to steer clear, you may have your biology to thank. Take an AncestryDNA^® + Traits test to find out more.

Why Do Mosquitoes Bite?

Mosquitoes hone in on their targets by looking for body heat and carbon dioxide. In fact, they can detect exhaled carbon dioxide from over 30 feet away. They seek out their next meal by following that scent, and once they find it, taste receptors on their feet help them determine whether to bite.

These pesky insects bite by piercing your skin with their proboscis—a straw-like mouth. They then inject saliva into your skin to prevent your blood from clotting while it drinks. The mosquito saliva contains over 100 specialized proteins to prevent your blood from clotting, make your blood vessels more permeable, and suppress your immune response.

A person's reaction to the saliva also causes mosquito bites to itch. Some people's skin responds to the bite with mild irritation and a small bump. Others may experience more extreme reactions. Skeeter syndrome, for example, is a localized allergic reaction to mosquito saliva. This condition is usually identifiable by the significant inflammation in the area between 8 and 10 hours after a bite. It can also present with fever, itching, and blisters. The good news is that mosquito bites typically last only a few days before healing completely.

Mosquitoes are attracted to people who:

• Have higher levels of carboxylic acids on their skin
• Have a higher metabolic rate
• Wear dark colors such as black or navy blue

While you can't change many reasons mosquitoes might target you, you can take precautions to avoid getting bitten. Consider:

• Using EPA-registered repellents
• Wearing protective clothing, including long-sleeved shirts and pants
• Avoiding outdoor activities at dusk and dawn, when mosquitoes are most active
• Removing standing water in your outdoor areas

Genetics and Mosquito Bites

Seeking concrete answers to why mosquitoes prefer to bite some people, the AncestryDNA team asked over 985,000 people, "When you are in an area with mosquitoes, how often do you get bitten?" Their responses, when compared to their genetic profiles, revealed over 1,990 DNA markers linked to getting bitten by mosquitoes.

Using these findings, the scientists calculated a polygenic risk score—a tool to predict how more or less likely you are to be bitten by a mosquito based on your genetics.

Looking at the results of their genetic study, the team concluded that the connection between getting bitten by mosquitoes has some genetic component, but is mainly controlled by environmental factors (like your local climate) and personal behaviors (like wearing protective clothing). That said, if you’re sitting outside with friends late at night, your genetics may be why you’re the mosquitos’ favorite meal, and your friends are left in peace.

What Else Does Science Say About Mosquito Bites?

Other biological—but nongenetic—factors influence one's overall attractiveness to mosquitoes. Pregnant people, for example, tend to attract mosquitoes more frequently. During late pregnancy, people exhale an estimated 21% more carbon dioxide, which increases their appeal to mosquitoes.

Pregnancy also causes other physiological changes that can attract mosquitos, such as a slight increase in body temperature. Between increased respiration and a warmer body temperature, pregnant individuals are easier for mosquitoes to find.

People actively exercising also attract mosquitoes for the same reasons: increased body temperature and exhaled carbon dioxide.

There's some truth behind the folktale that eating bananas attracts mosquitoes. Beer and bananas are the only dietary components that reliably increase mosquito attraction in specific targets. This boost in appeal may be due to the digestive process altering the metabolism in ways that affect the host's body odor. A study revealed that two mosquito species, Anopheles stephensi and A. gambiae, showed a significant increase in attraction to hand secretions one hour after the host consumed a banana.

Interesting Facts About Mosquito Bites

Not all mosquitoes bite people. Only female mosquitoes are attracted to humans because they seek protein in blood to develop their eggs. Even when blood was served in lab settings, male mosquitoes refused the meal. Instead, male mosquitoes prefer a diet of nectar and fruit juices.

During a meal, mosquitoes drink more than twice their body weight in blood. Despite this, it would take up to 1.2 million bites to completely drain a human's blood supply.

Mosquito bites and bed bug bites can be confused due to their similarities. Both typically result in itchiness and some degree of swelling. However, mosquito bites tend to swell up more based on a person's response to the saliva. Another difference is that mosquito bites appear more randomly across the body, while bed bug bites often occur in clusters that follow a straight line.

Wondering whether mosquitoes feast on you or avoid you for genetic reasons? Or maybe you sneeze when you look at the sun, or cilantro aversion? An AncestryDNA + Traits test can reveal whether you have these traits and more. If you've already taken a test, check out your answers with your Ancestry membership today.