The patenting of human genes has generated considerable controversy, both in the doctrinal field and in the legal and administrative. In the core countries, particularly the USA and the European Union, a favourable criterion to patentability has been increasing, contrasting with the criteria adopted by Latin American countries, which almost unanimously banned the patentability of genes and gene sequences. This issue not only has legal connotations, but also ethical issues come into play. Particularly in the USA, the recent decision of the Supreme Court in the Myriad case is part of a pro-patent movement, even when its superficial reading seems to be oriented in the opposite direction. In the European Union, the criterion that favours human intervention, whatever its gravitation in the results, tips the balance in favour of patentability.