Rapid suppression of drive for a parasitic B chromosome.
The persistence of parasitic B chromosomes in natural populations depends on both B ability to drive and host response to counteracting it. In the grasshopper Eyprepocnemis plorans, the B24 chromosome is the most widespread B chromosome variant in the Torrox area (Málaga, Spain). Its evolutionary success, replacing its ancestral neutralized B variant, B2, was based on meiotic drive in females, as we showed in a sample caught in 1992. In females collected six years later, mean B24 transmission ratio (k(B)) was 0.523, implying a very rapid decrease from the 0.696 observed in 1992. This shows that B24 neutralization is running very fast and suggests that it might most likely be based on a single gene of major effect.
Departamento de Genética, Universidad de Granada, Granada, Spain. fperfect@ugr.es
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Perfectti
J M
JM
Corral
J A
JA
Mesa
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Cabrero
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Bakkali
M D
MD
López-León
J P M
JP
Camacho
D000818:Animals; D002875:Chromosomes / Q000235:genetics*; D019143:Evolution, Molecular; D005260:Female; D005828:Genetics, Population; D006110:Grasshoppers / Q000235:genetics; D008297:Male; D008540:Meiosis / Q000235:genetics*