So she and her colleagues have instead looked for
venom genes in the genome of a close Latrodectus relative, the common house spider, Parasteatoda tepidariorum, which was reported on 31 July in BMC Biology by a team headed by Alistair McGregor of Oxford Brookes University in the United Kingdom.
Armed with the both the king cobra and Burmese python
genome the team was able to show that, despite previous hypotheses that
venom genes evolve «early»
in the lineage leading to snakes,
venom gene families do not duplicate early,
in fact the study shows that the rapid and extensive expansion of functionally important
venom toxin families is restricted to the venomous «advanced» snake lineage.