Recently developed approaches to creating genetically engineered anima
ls have expanded researchers' repertoire of methods to investigate the
roles of individual genes in the development of certain behaviors and
diseases, including alcoholism. For example, knockout mice, in which
single mouse genes have been inactivated have allowed scientists to as
sess the roles of those genes in mediating some of alcohol's effects.
This approach has been further refined using conditional gene knockout
technology, which allows the inactivation of a gene only in certain c
ells or during specific developmental periods. Alternatively, transgen
ic mice (i.e., mice that carry a foreign gene in addition to their own
genes) have been created in which researchers can activate or inactiv
ate the foreign gene at will. Although these genetic engineering techn
ologies have not yet been used extensively in alcohol research, they o
ffer great promise in analyzing the functions of genes that may be inv
olved in determining alcohol's effects on the body and the development
of alcoholism.