Properties and natural occurrence of maternal-effect selfish genes (Medea factors) in the Red Flour Beetle, Tribolium castaneum

Natural occurrence and properties of maternal-effect selfish genes, or Medea factors, in the Red Flour Beetle, Tribolium castaneum have been studied. The genes were found to be widespread in the wild population of the beetle samples collected in North and South America, Africa, Europe and southeast Asia. They were rare or not found in populations sampled in the Indian subcontinent and Australia. At least four distinct genetic loci were detected in at least two linkage groups that have the Medea pattern of differential mortality of genotypes in maternal families. Each M factor tested had similar properties of zygotic self-rescue and maternal lethality to larvae. However, M factors representing distinct loci did not show cross-rescue.