Sir

The drive to develop new human pluripotent stem-cell lines has attracted a new, exuberant cohort of researchers who may not be familiar with the regulations and standards governing donation of human tissue. Scientists should ask donors to agree to some basic rules for research involving induced pluripotent stem (iPS) cell lines derived from their tissue. This would help to prevent road blocks of the kind highlighted in your Editorial (Nature 460, 933; 2009) about Sabine Conrad and colleagues' Corrigendum to their paper 'Generation of pluripotent stem cells from adult human testis' (Nature 460, 1044; 2009).

The rules would cover sharing cell lines with other investigators, as in this case; carrying out large-scale genome sequencing; injecting iPS cells or their derivatives into animals; and patenting discoveries or commercial uses arising from iPS cells or derivatives, with no sharing of royalties with donors. Additional specific consent would be needed for allogeneic human transplantation or reproductive research using gametes derived from iPS cells. Permission might be needed to recontact donors about new research proposals.

The advent of human adult germline stem cells and iPS cells avoids ethical issues over the use of early human embryos. So, unlike human embryonic stem cells, there is not likely to be a shortage of donors for germline stem cells or iPS cells (except in the case of rare diseases). Given that iPS cell lines can be propagated indefinitely, they are likely to become widely used. But applications still require proper consent from the tissue donor.

The proposed minimum-consent criteria from tissue donors should help to maximize the scientific value of cell lines in realizing the promise of this technology.