Centromere-associated female meiotic drive entails male fitness costs in monkeyflowers.
Female meiotic drive, in which paired chromosomes compete for access to the egg, is a potentially powerful but rarely documented evolutionary force. In interspecific monkeyflower (Mimulus) hybrids, a driving M. guttatus allele (D) exhibits a 98:2 transmission advantage via female meiosis. We show that extreme interspecific drive is most likely caused by divergence in centromere-associated repeat domains and document cytogenetic and functional polymorphism for drive within a population of M. guttatus. In conspecific crosses, D had a 58:42 transmission advantage over nondriving alternative alleles. However, individuals homozygous for the driving allele suffered reduced pollen viability. These fitness effects and molecular population genetic data suggest that balancing selection prevents the fixation or loss of D and that selfish chromosomal transmission may affect both individual fitness and population genetic load.
Fishman
Lila
L
Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA. lila.fishman@mso.umt.edu
Saunders
Arpiar
A
D000483:Alleles; D001483:Base Sequence; D005075:Biological Evolution; D002503:Centromere / Q000502:physiology*; D020090:Chromosome Segregation; D032461:Chromosomes, Plant / Q000502:physiology*; D003433:Crosses, Genetic; D005819:Genetic Markers; D006579:Heterozygote; D006824:Hybridization, Genetic; D015810:Linkage Disequilibrium; D008540:Meiosis; D032241:Mimulus / Q000235:genetics* / Q000502:physiology; D008969:Molecular Sequence Data; D011110:Polymorphism, Genetic; D012091:Repetitive Sequences, Nucleic Acid; D012641:Selection, Genetic
D005819:Genetic Markers