Exon-Enriched Libraries Reveal Large Genic Differences Between Aedes aegypti from Senegal, West Africa, and Populations Outside Africa.
Aedes aegypti is one of the most studied mosquito species, and the principal vector of several arboviruses pathogenic to humans. Recently failure to oviposit, low fecundity, and poor egg-to-adult survival were observed when Ae. aegypti from Senegal (SenAae) West Africa were crossed with Ae. aegypti (Aaa) from outside of Africa, and in SenAae intercrosses. Fluorescent in situ hybridization analyses indicated rearrangements on chromosome 1, and pericentric inversions on chromosomes 2 and 3. Herein, high throughput sequencing (HTS) of exon-enriched libraries was used to compare chromosome-wide genetic diversity among Aaa collections from rural Thailand and Mexico, a sylvatic collection from southeastern Senegal (PK10), and an urban collection from western Senegal (Kaolack). Sex-specific polymorphisms were analyzed in Thailand and PK10 to assess genetic differences between sexes. Expected heterozygosity was greatest in SenAae FST distributions of 15,735 genes among all six pairwise comparisons of the four collections indicated that Mexican and Thailand collections are genetically similar, while FST distributions between PK10 and Kaolack were distinct. All four comparisons of SenAae with Aaa indicated extreme differentiation. FST was uniform between sexes across all chromosomes in Thailand, but were different, especially on the sex autosome 1, in PK10. These patterns correlate with the reproductive isolation noted earlier. We hypothesize that cryptic Ae. aegypti taxa may exist in West Africa, and the large genic differences between Aaa and SenAae detected in the present study have accumulated over a long period following the evolution of chromosome rearrangements in allopatric populations that subsequently cause reproductive isolation when these populations became sympatric.
['Dickson|Laura B|LB|', 'Campbell|Corey L|CL|', 'Juneja|Punita|P|', 'Jiggins|Francis M|FM|', 'Sylla|Massamba|M|', 'Black|William C|WC|']
D000330:Aedes D000354:Africa, Western D000818:Animals D019143:Evolution, Molecular D005091:Exons D015723:Gene Library D014644:Genetic Variation D059014:High-Throughput Nucleotide Sequencing D006801:Humans D017404:In Situ Hybridization, Fluorescence D007303:Insect Vectors D012675:Senegal D013785:Thailand
Aedes aegypti West Africa genome population genomics subspecies