Scientists decode deer tick genome after a decade-long research


After ten years of research, scientists finally managed to sequence the genome of Lyme-transmitting deer tick or blacklegged tick, Ixodes scapularis.  The study is a collective effort of an international team of 93 scientists from 46 institutions led by Catherine Hill, an entomologist of Purdue University.

Ixodes scapularis is the first tick species to have its genetic makeup decoded and sequenced successfully. The researchers were able to identify and sequence more than 24,000 genes which correspond to tick’s digestion and metabolism, ability to manipulate the host’s immune responses, and toxic elimination in the tick’s system. This study will spearhead more in-depth research on other species of ticks.

Lyme disease is caused by Borrelia burgdorferi, a corkscrew-shaped bacterium. Blacklegged ticks serve as vectors of the bacteria and can transfer it to the host by burrowing through the skin and sucking the blood of animals and incorporating the infected saliva on the blood stream. Ticks can stay in the host to suck blood for a few days or weeks and remain unnoticed. They can also expand to a great extent when feeding and are capable of consuming blood 100 times their body weight. If left untreated, the most common symptoms associated with Lyme disease are joint pain, facial paralysis, fatigue, memory loss, and heart palpitations. In the United States, it is estimated that around 300,000 people are suffering from Lyme disease and most of them are either undiagnosed or already in the late stage of diagnosis.

This breakthrough can pave the way for the development of new methods to control the blood-sucking parasite. This new knowledge about the genetic makeup of ticks will help scientists in formulating new and effective insecticides and repellents as well as vaccines to reduce the risk of Lyme disease and prevent the transmission of other pathogens in humans and animals.

Furthermore, genetic modification is now possible to manipulate the disease-carrying traits of ticks without having to decrease their population. According to entomologist R. Michael Roe of North Carolina State University, a possible “birth control pill” for ticks can be studied and developed after the researchers on a related study on ticks determined the hormone responsible for egg development in female ticks.

Source: reuters.com