Genes hold secret of survival of Antarctic 'antifreeze fish'

A genetic study of a fish that lives in the icy waters off Antarctica sheds light on the adaptations that enable it to survive in one of the harshest environments on the planet. (To see an audio slide show on the fish, please go to: http://publicaffairs.illinois.edu/slideshows/Antarctic%5FNotothenioids/). The study, in the Proceedings of the National Academy of Sciences, is the first to search the genome of an Antarctic notothenioid fish for clues to its astounding hardiness. There are eight families of notothenioid fish, and five of them inhabit the Southern Ocean, the frigid sea that encircles the Antarctic continent. These fish can withstand temperatures that would turn most fish to ice. Their ability to live in the cold and. oxygen-rich extremes is so extraordinary that they make up more than 90 percent of the fish biomass of the Southern Ocean.