Disgraced cloning scientist Hwang Woo-suk's controversial NT-1 "embryonic stem cell line" officially received a United States patent on Tuesday in a development that could reignite debate surrounding his research. The U.S. Patent and Trademark Office's (USPTO) public notification site confirmed the "human embryonic stem cell line prepared by nuclear transfer of a human somatic cell into an enucleated human oocyte" has been patented and subject to legal protection.