Recombinant DMA Advisory Committee - 
the rest of their lives. 
2. On the issue of efficiency of gene transfer there needed to be further 
clarification on how the investigators would scale up from the preclinical in 
vitro experiments to an entire human bone marrow transplant protocol. 
The investigators had provided details in Appendix A in this regard, but 
that clarification was still needed on the differences between the procedure 
and the conditions used to generate the in vitro data. 
3. In regard to the molecular analysis of the regenerated tumor, questions still 
exist concerning evidence that tumor cells can be transduced, injected into 
animals and recovered for analysis, which was not discussed despite the 
fact that a rat model for human AML has been established and studied 
extensively. 
Dr. Mclvor said that in the absence of in vivo results on tumor cell tagging and recovery, 
it was quite likely that marked cells could not be found in regenerated tumor and 
therefore the results of the experiment will be uninformative. However, because of the 
small risk associated with the procedure and the fact that useful information may be 
generated, he could recommend approval of the protocol with an addition to the 
informed consent document. He asked that the following statement be inserted into the 
informed consent document: 
"I understand that while useful information might be generated from my 
participation in this study, it is also possible that no useful information will be 
generated.” 
He said this was necessary to properly inform people participating in the study that there 
is a possibility that no meaningful information may result if tumor tagging does not 
occur. Further, he urged that the wording on the fourth line of page 111 of the mailing 
be changed to reflect that the virus containing the marker has been "extensively 
disabled," rather than "strongly disabled." Dr. Mclvor spoke with Dr. Childress in 
relation to the issues of the informed consent document and that Dr. Childress had been 
in complete agreement with him. 
Dr. McGarrity noted that Dr. Childress was absent because of the necessity to deal with 
departmental business at his institution. Dr. Childress sent a FAX which stated: 
"My review of the materials is not thorough enough or careful enough to justify a 
written evaluation. It is too impressionistic. LeRoy Walters will. I'm sure, cover 
thoroughly and carefully what I may have been able to provide." 
Recombinant DNA Research, Volume 14 
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