Parasites responsible for the lethal disease known as sleeping sickness may extend their reach beyond their traditional habitat in Africa due to genetic mutations, a recent study indicates.
The research highlights how climate change and efforts to manage tsetse fly populations, which transmit the disease, could lead to molecular modifications in the parasites that cause sleeping sickness—a condition that can be deadly if not treated.
The parasites, referred to as African trypanosomes, are typically spread by tsetse flies in the sub-Saharan region of Africa. Nevertheless, studies suggest that these parasites have adapted to infect hosts without relying on tsetse flies.
Recent discoveries have identified new strains that can infect animals in Asia, South America, and southern Europe. Researchers warn that this may also apply to strains that target humans.
Previously, the specific molecular changes contributing to these newer, more aggressive forms of the parasites were not fully understood.
A research team led by experts at the University of Edinburgh has uncovered that modifications in crucial genes have streamlined the life cycle of these organisms, allowing them to proliferate beyond their typical geographical limits.
The researchers examined the genetic structure of over 80 trypanosome samples collected from humans, tsetse flies, cattle, and various other animals. This data was utilized to develop a family tree depicting the relationships among different parasite strains.
Following this, the team employed a gene-editing technique known as CRISPR-Cas9 to investigate whether various molecular alterations contribute to the parasite’s ability to spread independently of tsetse flies. This process uncovered multiple mutations in genes essential for their life cycle.
Identifying the specific genes and mutations involved may be crucial for detecting and addressing emerging aggressive strains of these parasites, according to the researchers.
The findings, published in the journal Nature Communications, received support from the Wellcome Trust, the Medical Research Council, the Bill & Melinda Gates Foundation, and the Flemish Government. Collaborating researchers included experts from the University of York, KU Leuven, the Institute of Tropical Medicine in Antwerp, and the French Agency for Food, Environmental and Occupational Health & Safety.
