Laboratory rearing of Anopheles arabiensis: impact on genetic variability and implications for Sterile Insect Technique (SIT) based mosquito control in northern Sudan

Malaria Journal

Research

Elamin El Rayah¹  Kamal Ibrahim²  Colin Malcolm³  Badria El-Sayed⁴  Rasha Siddig Azrag⁵ 

[1] Department of Zoology, Faculty of Science, University of Khartoum, Khartoum, Sudan;Department of Zoology, Southern Illinois University Carbondale, 62901, Carbondale, IL, USA;School of Life and Medical Sciences, University of Hertfordshire, Hatfield, UK;Tropical Medicine Research Institute, National Centre for Research, Khartoum, Sudan;Tropical Medicine Research Institute, National Centre for Research, Khartoum, Sudan;Department of Zoology, Faculty of Science, University of Khartoum, Khartoum, Sudan;

关键词: Anopheles arabiensis;    Mosquitoes;    Colonization;    Genetic variability;    Microsatellites;    Sterile insect technique;   

DOI  :  10.1186/s12936-016-1484-2

 received in 2016-05-24, accepted in 2016-08-11,  发布年份 2016

来源: Springer

【 摘 要 】

BackgroundMosquito colony populations often show significant changes in their population genetic make-up compared to the field populations that were used as founding source. Most of the changes that have been reported are indicators of depletion in the overall genetic diversity of the colony populations. The Sterile Insect Techniques programme of mosquito control that is underway in Northern Sudan uses sterilized males produced from a laboratory-maintained colony population. The genetic diversity of an advanced generation of this colony population was quantitatively assessed and compared to the field population from which the colony was derived.MethodsAnopheles arabiensis mosquito samples from the 13th generation of the colony, and from the locality that was the source of the first generation of the colony, were genotyped at 11 microsatellite loci distributed throughout the species’ genome. Standard population genetic analyses were carried out to quantify and compare their population genetic make-up and diversities.ResultsThe colony samples showed significant reduction in the total number of alleles, the numbers of rare and private alleles, and the fractions of heterozygote individuals at all the loci. The pattern of change is consistent with the expected effect of the use of a small number of mosquitoes when the colony was established. Departure from Hardy–Weinberg equilibrium in the direction of homozygote excess was observed at some loci and attributed to the presence of null-alleles.ConclusionsThis study highlights the need for broad sampling when initiating colony populations and for ongoing assessment of the population genetic make-up of colony populations. Previous assessments of survivorship, dispersive behaviour and swarm formation indicate that the inbreeding and reduced genetic variability reported in this study may not have had direct fitness consequences yet. However, noting the lessons learned in other SIT programmes about the impact of colonization on male sexual behaviour and longevity, as well as other inbreeding related adverse effects, a systematic investigation of these potential effects is recommended because they have direct impact on the ultimate success of the programme.

【 授权许可】

CC BY   
© The Author(s) 2016