THE UNIVERSITY OF TEXAS MEDICAL BRANCH 
GALVESTON, TEXAS 77550 
DEPARTMENT OF HUMAN BIOLOGICAL CHEMISTRY & GENETICS Area Code 409 
Division of Cell Biology 761-2761 
October 19, 1984 
Di rector 
Office of Recombinant Activities 
Building 31, Room 3B10 
National Institutes of Health 
Bethesda, MD 20205 
Sirs: 
I am writing in strong objection to Mr. Jeremy Rifkin's proposal to ban 
incorporation of genetic materials into the germline across species lines in 
mammals. In the first place, Mr. Rif kin offers no evidence that such experi- 
ments involve any risk to the public--and it is on the basis of risk 
assessment that the RAC is charged with making its decisions. Instead, Mr. 
Rifkin offers a set of labored philosophical statements about the inherent 
rights of species to a separate identity--a subject more suited to the 
classroom than to a regulatory agency. 
If adopted, however, Mr. Rifkin's proposal would have a most far- 
reaching adverse impact on a promising future approach to treatment of human 
genetic diseases. Some of those diseases caused by enzyme deficiencies in a 
well-defined target area may soon prove amenable to treatment by somatic gene 
therapy, in which the wild type gene would be introduced into somatic cells 
of the affected organs. However, those diseases whose defect involves a 
more widespread or unknown target could not be treated in this way, but might 
be ameliorated by introduction of the wild type gene into eggs before in vitro 
fertilization. Obviously, detailed animal experiments would have to precede 
any possible human trials of such a scheme. Since animal models of only a 
few genetic diseases are avilable, most such experiments would attempt to 
detect expression of exogenous genes against a wild type background. To 
establish definitively the nature of any increased expression, heterologous 
genes would have to be used. But it is precisely those experiments which Mr. 
Rifkin now seeks to ban. Thus, his proposal would forever seal off this 
promising area of future research. 
[ 546 ] 
