 Design-based motivations for selection, however, have been the subject of a great deal more debate. This discussion largely mirrors (or is subsumed by) many of the discussions had regarding the ethics of selective reproductive technologies, such as pre-implantation and pre-natal genetic diagnosis, and such topics as sex selection and human enhancement (see the entries on  pregnancy, birth &amp; medicine,  and  eugenics).  For, although in the context of gamete donor selection there are no embryos or fetuses involved, nor genetic manipulation performed, there has been much focus on questions of: