Genetic variants linked to dengue fever susceptibility

A new study has identified two genetic variants linked with an increased susceptibility to severe dengue fever.

The study, undertaken by researchers located in South East Asia, was published in the journal Nature Genetics, according to MedicalNewsToday.com.

Epidemiological investigations have shown that certain populations are more susceptible to dengue, which suggested that there may be something in an individual’s genetic makeup that renders them more exposed to the illness.

In order to test this theory, investigators from the Wellcome Trust Vietnam Research Program, Singapore’s Agency for Science, Technology and Research, and the Oxford University Clinical Research Unit, undertook the first genome-wide association investigation of dengue.

The researchers analyzed the differences in the genomes of children with severe dengue against control populations. After examining the DNA of 2,008 children with severe dengue and comparing it against 2,018 controls and then replicating their results with a follow-up sample, they found changes in the DNA code within two genes, MICB on chromosome six and PLCE1 on chromosome 10. These two genes appear to regulate susceptibility to dengue shock syndrome or the effects of severe dengue, MedicalNewsToday.com reports.

Dengue is the most common mosquito-borne infection in the world after malaria. It affects approximately 100 million people in the tropical and sub-tropical regions of the world every year.

Dengue symptoms include a mild to incapacitating fever, headache, rash and joint pain. Certain strains of the illness are hemorrhagic and can cause death, but they are rare in comparison to those that cause flu-like symptoms. There is no treatment or clinically-approved vaccine for the disease.

The hemorrhagic form of the disease results in bleeding, low platelet counts and blood plasma leakage into surrounding tissue. The bleeding can result in dengue shock syndrome, a form of hypovolemic shock during which blood and fluid loss can leave the heart unable to pump sufficient blood throughout the body.