Individuals live in a ‘universe of social and legal norms’, and the family is one entity in which the web of mutual, but often conflicting, rights and obligations exists. Interdependence is at the core of most families, and nowhere is this more apparent than in the context of genetics, since we inherit our genetic identity from our progenitors, with whom we will inevitably share certain genetic traits. Revelation of a genetic disease carried by one member of the family can, therefore, mean that other direct-line family members could be affected, although not necessarily, as there are often other variables at play. This biological reality gives rise to a number of legal (and ethical) dilemmas. Should there be a duty on an individual to share their personal genetic information with any family member? If so, what would the nature of that duty be? Should it be confined to a procedural obligation on the part of the treating healthcare professional to encourage and support the individual proband to disclose their diagnosis with those potentially affected, but without any possible enforcement? Should there be a substantive right for family members to be informed, and a consequential duty on either the proband, or their doctor, to inform? Or is the respective autonomy of each family member dependent upon a core of relational interdependence, in which the law has a limited role to play?

In this chapter, I explore how some of the themes inherent in John Eekelaar’s work can be of use in thinking about the sharing of genetic information, from a family law perspective. First, I lay out the current legal position regarding the sharing of medical information which, despite a certain aspiration towards a communitarian approach, remains firmly attached to liberal individual ideology. The limited case law in this area relies upon tort law principles to find a balance between the two. I then engage with the debate on whether genetic information merits being treated differently in law to other types of information to justify prioritising the communitarian approach over fundamental principles such as individual autonomy and the right to privacy. Logically, this could extend to imposing upon the probands themselves a duty to disclose a relevant diagnosis to family members.