On 1 April 2005, with the implementation of the Human Fertilisation and Embryology Authority (Disclosure of Donor Information) Regulations 2004, United Kingdom law was changed to allow children born through gamete donation to access details identifying the donor. Drawing on trends in adoption law, the decision to abolish donor anonymity was strongly influenced by a discourse that asserted the ‘child's right to personal identity’. Through examination of the donor anonymity debate in the public realm, while adopting a social constructionist approach, this article discusses how donor anonymity has been defined as a social problem that requires a regulative response. It focuses on the child's ‘right to personal identity’ claims, and discusses the genetic essentialism behind these claims. By basing its assumptions on an adoption analogy, United Kingdom law ascribes a social meaning to the genetic relatedness between gamete donors and the offspring.