Genetic selection of a flavivirus-refractory strain of the yellow fever mosquito Aedes aegypti.
Two inbred (isofemale) Aedes aegypti mosquito lines were derived that manifested a resistant or susceptible phenotype following ingestion of yellow fever virus; lack of virus movement from the midgut defined the resistant phenotype. Other flaviviruses, including dengue 1-4, Uganda S, and Zika, viruses behaved in a similar fashion in the two mosquito lines. Crosses between the two lines produced progeny that were of intermediate susceptibility, indicating codominance; F2 backcrosses to the parents yielded results consistent with a major controlling genetic locus and provide evidence of a second locus capable of modulating the phenotype of the major gene. The rapid selection necessary to fix the susceptible and refractory phenotypes support the hypothesis of a single major controlling locus. Viral movement across the midgut is likely to be governed by a single major gene and modifying minor genes or a group of closely linked genes. These inbred mosquito lines will be useful in discovering the molecular basis for flavivirus resistance in Ae. aegypti.
Miller
B R
BR
Medical Entomology-Ecology Branch, Centers for Disease Control, Fort Collins, Colorado.
Mitchell
C J
CJ
D000330:Aedes / Q000235:genetics / Q000821:virology*; D000818:Animals; D003716:Dengue Virus / Q000235:genetics / Q000302:isolation & purification; D005260:Female; D005416:Flavivirus / Q000145:classification / Q000235:genetics*; D006801:Humans; D007178:Inbreeding; D007303:Insect Vectors / Q000235:genetics / Q000821:virology*; D008253:Macaca mulatta; D009549:Nigeria; D010641:Phenotype; D015005:Yellow fever virus / Q000235:genetics / Q000302:isolation & purification; D000071244:Zika Virus / Q000235:genetics / Q000302:isolation & purification