Concerns are emerging about the protection of individuals who take part in genetic research involving biobanks. We used several items of a questionnaire sent to 48 French research ethics committees (RECs) to investigate the means by which they evaluate the constitution and use of biobanks, and the elements on which conclusions were based. Most RECs felt they should evaluate the constitution of biobanks in protocols, but not all did so in practice. Harmonization of the competence of RECs for evaluating biobanks is required, particularly concerning information, consent, the duration of sample conservation and the communication of research results. Our results, together with those of others, demonstrate the need to develop rules and guidelines based on common ethical approaches, particularly in the European environment.