New research investigates the genetic basis of our attractiveness to mosquitos. Scientists hope to therapeutically exploit these genetic relationships in the future. Source: Wikimedia Commons
Mosquito-borne illnesses are serious worldwide problems, causing over one million worldwide deaths per year. These diseases, including malaria and dengue, are transmitted through mosquito bites (1). Female mosquitos require blood meals for egg production, and studies have shown that mosquitos are more attracted to some people than others. These studies demonstrate that diverse factors like body mass index, beer drinking, and pregnancy among females are associated with more frequent mosquito biting (1). However, a pilot study recently conducted by British researchers at the London School of Hygiene and Tropical Medicine, indicates that there is an underlying genetic component to our attractiveness to mosquitos.
The study, published in the peer-reviewed journal PLOS ONE on April 22, attempts to investigate the relationship of each human’s unique body odor to mosquito attractiveness. The study was conducted using special Y-shaped tubes called Y-tube olfactometers (1). The researchers conducted trials with 18 identical and 19 non-identical female twins. In each trial, there were four different combinations of odors that could be presented to the mosquitoes: 1) twin A vs clean air; 2) twin B vs clean air; 3) twin A vs twin B; and 4) clean air vs clean air. Combinations 1, 2, and 4 were used for control purposes; the study was chiefly concerned with the comparison between identical and non-identical twins in combination 3 (1).
To compare the identical and non-identical groups, each twin placed her hand within a limb of the Y-tube, and the tube carried each participant’s unique odor down the tube by air flow. At the other end of the tube, twenty Aedes aegypti mosquitoes, belonging to the species that transmits Dengue, were released, and the number of mosquitoes that followed the odor of one twin versus another was counted (1).
The trails indicated that identical twins were more similar in attractiveness to mosquitos than non-identical twins. In fact, according to the study’s results, the likelihood of being bit by a mosquito is as genetically linked as commonly known heritable traits like height and IQ (2). Moreover, the study corroborates the notion that attractiveness to mosquitos is governed by a genetically determined body odor. In the future, scientists hope to exploit this new knowledge to develop methods to control mosquitos better. Some researchers envision “a pill which will enhance the production of natural repellents by the body and ultimately replace skin lotions” (2). By establishing a better understanding of the genetic basis of insect biting, we can create new ways to prevent insect-borne illnesses and save lives.
References:
- Fernández-Grandon et al. (2015, April 22). Heritability of Attractiveness to Mosquitos. Retrieved May 3, 2015, from http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0122716
- London School of Hygiene & Tropical Medicine. (2015, April 22). Genes make some people mosquito targets, twin pilot study shows. Retrieved May 3, 2015, from http://www.sciencedaily.com/releases/2015/04/150422142407.htm