Children created through mitochondrial replacement techniques (MRTs) are commonly presented as possessing 50% of their mother’s nuclear DNA, 50% of their father’s nuclear DNA and the mitochondrial DNA of an egg donor. This lab-engineered genetic composition has prompted two questions: Do children who are the product of an MRT procedure have threegeneticparents? And, do MRT egg donors have parental responsibilities for the children created? In this paper, I address the second question and in doing so I also address the first (...) one. First, I present a brief account of mitochondrial diseases and MRTs. Second, I examine how MRTs affect the numerical identity of eggs and zygotes. Third, I investigate two genetic accounts of parenthood and MRT egg donation. Fourth, I explore three causal accounts of parenthood and MRT egg donation. My conclusion is that, under the appropriate circumstances, MRT egg donors are parentally responsible for the children created under genetic accounts of parenthood and under causal accounts of parenthood. (shrink)

Speciesist or biological accounts of moral status can be defended by showing that all members of Homo sapiens have a moral status conferring property. In this article, I argue that the most promising defense locates the moral status conferring property in the relational property of being biologically tied to other humans. This requires that biological ties ground moral obligations. I consider and reject the best defenses of that premise. Thus, we are left with compelling evidence that biological ties and membership (...) in a biological category like “species” ground neither moral obligations nor moral status. Because it is crucial to account for the moral significance of family bonds, I conclude by describing the sense in which biological ties matter morally. (shrink)