In January's issue, geneticist Pier Paolo Pandolfi of the Memorial Sloan-Kettering Cancer Center in New York describes the cancer-causing POK erythroid myeloid ontogenic gene, calling it Pokemon.

The gene in question is part of the POK gene family that encodes proteins that turn off other genes. POK proteins are critical in embryonic development, cellular differentiation and oncogenesis, according to the National Cancer Institute.

Nonplussed by the rush of headlines like "Pokemon causes cancer," Nintendo subsidiary Pokemon USA threatened legal action against the center to have the name of its popular game and trading-card series disassociated from the gene, the latest issue of Nature reports. The cancer center has complied with Pokemon's demands and now refers to the gene by the much-less-catchy moniker Zbtb7, Nature reports.

This is not the first time researchers have dipped into the world of gaming for a research nickname. The Sonic hedgehog gene was named after Sega's speedy mascot in 1993. Sega has never sued over the matter, even though mutations in the developmental gene can lead to a number of brain and facial defects, including cyclopia.

Brendan Sinclair of GameSpot reported from San Francisco.