The genetic elements, called Mavericks, have been detected in a wide range of animals, both invertebrates and vertebrates, and they display many features found in the genomes of viruses. Given those properties, researchers suspect that Mavericks — and similar elements, including some not yet discovered — may have mediated horizontal gene transfers throughout the history of life.
Selfish, Virus-Like DNA Can Carry Genes Between Species
Some roundworms carry a genetic element that is so fascinatingly selfish, the survival of offspring hinges on inheriting at least one copy of it. It contains a duo of genes, one encoding a toxic protein and one encoding an antidote that neutralizes the toxin. A mother worm that carries this element deposits the toxin in her eggs. When the eggs are fertilized, only offspring that can express the antidote gene survive. It is as if the toxin-antidote element has taken the worm’s genome hostage to ensure its propagation.
Biology can be strange and ruthless. Anyone reminded of the Thufir Hawat, Mentat and Master of Assassins to House Atreides, character in the Dune SciFi novel.