Leishmania
species
are protozoan parasites that are transmitted by a bite from a sandfly. These
parasites are found in 88 countries and infect an estimated 12 million people
worldwide. Genome sequencing of certain Leishmania
species has been, but not on Leishmania
donovani even though it is considered the most important Leishmania species in public health. Attempts
to eliminate L. donovani from India
have become a more difficult task due to drug resistant strains of L. donovani emerging. This study done by
Downing et al. (2011) was performed to better understand L. donovani genome to enhance public health intervention
strategies.
A high-quality draft of
Leishmania donovani genome was
created based off of isolates of L.
donovani collected from 17 infected patients. The reference genome was used
to map out natural variation data. After generating the genome sequences for
each of the 17 parasite sample, genome-wide single-nucleotide polymorphisms
(SNPs) and structural variation (SV) were revealed and genes with differential
patterns in antimonial resistant and susceptible samples were recognized. The
variation of SNPs was limited in parasite strains that were antimonial
resistant (Downing et al. 2011).
This study showed that
there is a correlation between genome-wide single-nucleotide polymorphisms and drug-resistant
strains of Leishmania donovani. More
sensitive and powerful approaches to observing genomic diversity should be
performed in order to further research L.
donovani and other Leishmania species’
drug resistance and how genomes are correlated (Downing et al. 2011).
This article relates to
the study by Guevara et al. (1994) “Presence of Leishmania braziliensis in blood samples from cured patients or at
different stages of immunotherapy” because Guevara et al (1994) studied the
presence of a Leishmania species in
humans after being treated for the infection and Downing et al. (2011)
researched how drug resistance in Leishmania species is correlated with genome.
Citation
T. Downing, H.
Imamura, S. Decuypere, T. Clark, G. Coombs, J. Cotton, J. Hilley, S. Doncker,
I. Maes, J. Mottram, M. Quail, S. Rijal, M. Sanders, G. Schonian, O. Stark, S.
Sundar, M. Vanaerschot, C. Hertz-Fowler, J. Dujardin, M. Berriman, 2011, Whole
genome sequencing of multiple Leishmania
donovani clinical isolates provides insights into population structure and
mechanisms of drug resistance, Genome
Research, 21: 2143-2156
-Kaitlin Smith
