washington

An advocacy group is challenging two proposed in utero gene-therapy experiments due to be discussed today (24 September) and tomorrow by the Recombinant DNA Advisory Committee (RAC) of the National Institutes of Health.

In a letter sent to the RAC last week, the Boston-based Council for Responsible Genetics charges that the in utero method, proposed by gene-therapy pioneer French Anderson, professor of biochemistry and paediatrics at the University of Southern California School of Medicine, leads “farther down the slippery slope to eugenics”.

But Anderson said on Monday that the council's criticism was “welcome”, and that, while he judges the risk of germline modification in his experiments to be minute, he has submitted his proposals “in order to have a public debate”.

In the council's letter to the RAC, Wendy McGoodwin, its executive director, warns that the proposed experiments risk making modifications to the fetal germ line that would be passed on to succeeding generations.

The RAC currently refuses to consider proposals aimed at modifying the germ line. The Anderson proposals do not seek to do this, but inadvertent germline modification is an admitted risk of in utero therapy. McGoodwin urges the committee “to tell Dr Anderson that the RAC does not consider in utero gene therapy to be an acceptable subject for research”.

The letter is among 70 pages of public comments, most of them negative, that the RAC has received in response to a public notice of the meeting.

Of Anderson's in utero proposals, one aims to treat α-thalassaemia, an error of haemoglobin synthesis, and the other severe combined immunodeficiency caused by adenosine deaminase deficiency (see Nature 395, 8; 1998). Neither protocol is ready for use in humans. At least two years of vector development and animal studies are necessary first, says Anderson.