Nine species of Anopheles of the subgenera Nyssorhynchus and Anopheles were
analysed using isoenzymatic markers and the DNA mitochondrial control region in order to
ascertain the intra e inter-specific genetic differences that may be related to each species
vectoring ability, and to try to understand the parental relationships among them. Eight
systems (EST, LAP, IDH, MDH, HK, ME, PGM and PGI), in starch and starch-agarose gel
with specific buffers and staining were employed for the isoenzymatic analysis. The
findings revealed that of the 13 analysed loci, nine were polymorphic (EST1, EST5, LAP1,
LAP2, IDH1, MDH1, HK3, ME1, PGM). Of the nine studied species, A. albitarsis from
Maruanum presented the highest polymorphism (P = 53.8%). Nevertheless, A. darlingi
from Macapá showed higher heterosygosity (Ho = 0.167 ± 0.071 and He = 0.173 ± 0.061).
The genetic structure analysis, based on the Wright statistics for the populations of A.
albitarsis, A. darlingi and A. benarrochi showed that the loci presented high genetic
structuring (Fst = 0.082, Fst = 0.110 and Fst = 0.016, respectively). Nonetheless, the genetic
distance in populations of A. darlingi, A. albitarsis and A. benarrochi showed great
similarity. Considering all analysed species populations, the genetic distance was greater,
ranging from 0.003 to 1.144. Mitochondrial DNA control region data showed little
difference being variation observed on the nucleotidic composition as to the adenine (A)
and timine (T) content in the species of the two subgenera. Subgenus Nyssorhynchus was
the one presenting higher A and T composition indicating higher polymorphism, due
possibly to a higher mutation rate. Inter-specifics nucleotidic distance ranged from 0.6 to
44.2%, indicating higher genetic divergence when compared with the isoenzymatic data.
Mitochondrial DNA and isoenzymatic data from the studied species showed that A.
oswaldoi and A. rangeli were the most genetically similar.
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