Parasites and Vectors (2020) 13 (253) - Genetic diversity and

Abraham Mayoke, Shadrack M. Muya, Rosemary Bateta, Paul O. Mireji, Sylvance O. Okoth, Samuel G. Onyoyo, Joanna E. Auma and Johnson O. Ouma (2020)
Genetic diversity and phylogenetic relationships of tsetse flies of the palpalis group in Congo Brazzaville based on mitochondrial cox1 gene sequences
Parasites and Vectors 13 (253)
Abstract:
Background
Despite the morphological characterization established in the 1950s and 1960s, the identity of extant taxa that make up Glossina fuscipes (s.l.) in the Congo remains questionable. Previous claims of overlap between G. fuscipes (believed to be G. f. quanzensis) and G. palpalis palpalis around Brazzaville city further complicate the taxonomic status and population dynamics of the two taxa. This study aimed to determine the phylogenetic relationships between G. fuscipes (s.l.) and G. p. palpalis and to assess genetic variation among G. fuscipes (s.l.) populations in Congo Brazzaville.
Methods
We collected 263 G. fuscipes (s.l.) from northern and central regions, and 65 G. p. palpalis from southern part of the country. The mitochondrial cytochrome c oxidase subunit 1 (cox1) gene was amplified using taxa-specific primer pairs. Sequence data were analyzed in DnaSP and Arlequin to assess the genetic diversity, differentiation and demographic history of G. fuscipes (s.l.) populations.
Results
The general BLAST analysis yielded a similarity of 99% for G. fuscipes (s.l.) and G. p. palpalis. BLASTn analysis for G. fuscipes (s.l.) showed > 98% identity with GenBank sequences for G. fuscipes (s.l.), with BEMB population showing 100% similarity with G. f. fuscipes. Glossina fuscipes (s.l.) populations showed high haplotype diversity (H = 46, Hd = 0.884), moderate nucleotide diversity ( = 0.012) and moderate (F_ST = 0.072) to high (F_ST = 0.152) genetic differentiation. Most of the genetic variation (89.73%) was maintained within populations. The mismatch analysis and neutrality tests indicated recent tsetse population expansions.
Conclusions
Phylogenetic analysis revealed minor differences between G. fuscipes (s.l.) and G. p. palpalis. Genetic diversity of G. fuscipes (s.l.) was high in the populations sampled except one. Genetic differentiation ranged from moderate to high among subpopulations. There was a restricted gene flow between G. fuscipes (s.l.) populations in the north and central part of the country. Genetic signatures based on cox1 showed recent expansion and recovery of G. fuscipes (s.l.) populations from previous bottlenecks. To fully understand the species distribution limits, we recommend further studies involving a wider sampling scheme including the swampy Mossaka focus for G. fuscipes (s.l.) and the entire range of G. p. palpalis in South Congo.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Full text of article
Database assignments for author(s): Paul Odhiambo Mireji

Research topic(s) for pests/diseases/weeds:
molecular biology - genes

---

Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Glossina palpalis		Congo-Republic
	Glossina fuscipes		Congo-Republic