These reports were widely quoted in media as "risks to food security" and threats to "gene banks" maintaining biodiversity. This was also emphasized because such a contamination was detected in Mexico, which is also the primary centre of genetic diversity for maize. Environmentalist groups like Greenpeace and Friends of the Earth took up the issue and amplified their call for a moratorium or an outright ban on GM crops. In january 2002, it reported in Nature biotechnology, that research conducted at CIMMYT did not confirm the transfer of transgenes from GM maize to either the local Merxican varieties or to any of the historical accessions in its extensive gene bank.