Sir

The potential for causing mischief by carrying out genetic analysis on an estimated 283 million archived tissue samples has become the focus of the US National Bioethics Advisory Commission.

French-Canadians living in Maine or Japanese-Americans living in California might learn about increased susceptibility to certain genetic traits, including disease predispositions, without any member from these groups consenting to participate in such analyses. Similarly, tribal customs might be disregarded in handling surgical or post-mortem remains. This had led to proposals for “community consultation”1.

In a News story, “‘Group debate’ urged for gene studies”2, Meredith Wadman cited a study of increased heritable susceptibility to colon cancer among Ashkenazi Jews as the trigger for this recommendation3. I should like to emphasize that, rather than ignoring the Ashkenazi Jewish community, this study has been a model for community consultation.

The study was carried out following population genetic studies of heritable susceptibility to Canavan's disease and to breast cancer (from inheritance of the BRCA2 6174delT mutation) among Ashkenazi Jews4,5. The participants in these studies were Ashkenazi Jewish people who had sought carrier testing for Tay-Sachs disease and cystic fibrosis. Approval of the institutional review board was obtained and subjects provided specific consent for anonymous population genetic studies of heritable susceptibility to these conditions. Samples were rendered anonymous upon receipt in the laboratory so that they could no longer be linked to their identifiers.

The results of the BRCA2 study received widespread coverage in the press and on television. Results of this study were presented at national scientific meetings and at leadership meetings of Jewish organizations. Letters about heritable susceptibility to disease among Jews were sent to synagogues and Jewish community centres. In the face of all this publicity, individuals have continued to provide their consent for such analyses both before and after the colon cancer study, and 1,600 DNA samples have been accumulated. Indeed, as the director of the genetic screening programme and the population genetic registry upon which these studies were based, I can assume only that the participants who spoke to physicians and counsellors in my programme and provided informed consent were acting as representatives of their community.

The intention of these studies was to benefit rather than create mischief for the Ashkenazi Jewish community. Because the colon cancer study was based on a relatively small sample and because of concern about unfair genetic discrimination, I expressed caution about lowering the threshold for offering genetic testing until the risks of being a carrier were more precisely quantified6. On the other hand, carrier screening for Canavan's disease has become standard. The usefulness and limitations of heterozygote testing for BRCA2, along with BRCA1, have been validated in a series of other studies for people with a family history of breast cancer.

Throughout this time, serving the needs and maintaining the trust of the Ashkenazi Jewish community have been the paramount concerns of my programme.