Patentability of inventions related to biotechnology and genetics has been one of the most challenging issues in patent law. One of these challenges is whether patenting products in which natural components are used is correct? Can we put human genes in the ownership of certain individuals? In addition, exercising exclusive rights arising from patents will limit the access of people, in particular, patients, doctors and researchers to the subject of patents. The decision of the US Supreme Court in Association for Molecular Pathology v. Myriad Genetics has put an end to many controversies and debates about isolated DNA sequences. The Supreme Court held that merely isolating genes that are found in nature does not render the invention patentable. Analyzing this decision, this article examines the patentability of DNA in Europe and USA.