Century-old malaria parasite puzzle solved as ape origin traced

Date:
April 6, 2022
Source:
University of Edinburgh
Summary:
Scientists have solved a 100-year-old mystery about the evolutionary
links between malaria parasites that infect humans and chimpanzees.



FULL STORY ========================================================================== Scientists have solved a 100-year-old mystery about the evolutionary
links between malaria parasites that infect humans and chimpanzees.


==========================================================================
They have discovered that the parasite P. malariae- one of six species
that spreads malaria among humans - originated in African apes before
evolving to infect people.

While it is often associated with mild disease, if untreated P. malariae
can cause long-lasting, chronic infections that may last a lifetime, researchers say.

The evolutionary puzzle has its origins in the 1920s when scientists
identified chimpanzees infected by parasites that appeared identical to
P. malariae under a microscope.

It was thought both parasites belonged to the same species, but - until
now - this could not be verified as the genetic make-up of the chimpanzee strain had never been studied.

Now, scientists at the University of Edinburgh, in collaboration with colleagues at the University of Pennsylvania, USA, have used leading
edge techniques to study the parasites' DNA.



==========================================================================
They have found that there are, in fact, three distinct species. One
species - P. malariae - infects mainly humans, while the two others
infect apes.

One of the two ape-infecting parasites was found in chimpanzees,
gorillas and bonobos across Central and West Africa. This previously
unknown species is only distantly related to the human parasite.

The other ape parasite is much more closely related to the one that
infects humans. Knowing this enabled researchers to make detailed
comparisons of the genetic diversity of the two species.

This revealed that the human malaria parasite population went through
a genetic bottleneck, where its population temporarily shrank and most
of its genetic variation was lost.

A likely explanation for this is that P. malariae was originally an
ape parasite, but a small number of parasites switched hosts to begin
infecting humans, the team says.

The study, published in the journal Nature Communications, was funded
by the National Institutes of Health.

Lead author Dr Lindsey Plenderleith, of the University of Edinburgh's
School of Biological Sciences, said: "Among the six parasites that cause malaria in humans,P. malariae is one of the least well understood. Our
findings could provide vital clues on how it became able to infect people,
as well as helping scientists gauge if further jumps of ape parasites
into humans are likely."

========================================================================== Story Source: Materials provided by University_of_Edinburgh. Note:
Content may be edited for style and length.


========================================================================== Journal Reference:
1. Lindsey J. Plenderleith, Weimin Liu, Yingying Li, Dorothy E. Loy,
Ewan
Mollison, Jesse Connell, Ahidjo Ayouba, Amandine Esteban, Martine
Peeters, Crickette M. Sanz, David B. Morgan, Nathan D. Wolfe, Markus
Ulrich, Andreas Sachse, Se'bastien Calvignac-Spencer, Fabian H.

Leendertz, George M. Shaw, Beatrice H. Hahn, Paul M. Sharp. Zoonotic
origin of the human malaria parasite Plasmodium malariae
from African apes. Nature Communications, 2022; 13 (1) DOI:
10.1038/s41467-022-29306-4 ==========================================================================

Link to news story: https://www.sciencedaily.com/releases/2022/04/220406101658.htm

--- up 5 weeks, 2 days, 10 hours, 50 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (1:317/3)