"In the paper, researchers led by Junjiu Huang, a gene-function researcher at Sun Yat-sen University in Guangzhou, tried to head off such concerns by using 'non

"In the paper, researchers led by Junjiu Huang, a gene-function researcher at Sun Yat-sen University in Guangzhou, tried to head off such concerns by using 'non-viable' embryos, which cannot result in a live birth, that were obtained from local fertility clinics." where are the non-viable embryos coming from?