By late next year, doctors may be able to quickly detect viral,
bacterial, and genetic diseases using a new "gene-amplification"
technology. Like the polymerase chain reaction (PCR) developed by Cetus
Corp. of Berkeley, Calif., the new "Q-beta replicase" technology involves
taking infinitesimal bits of genetic material from cells, viruses, or
bacteria, and chemically copying them until enough is available to make a
diagnosis. Both techniques take less than an hour. Each one is expected
to be used commercially to detect HIV genes. Current tests detect
antibodies to the virus, which often do not show up until months after
infection. Gene-Trak Systems of Framingham, Mass., a joint venture of
Integrated Genetics Inc. and Amoco Corp., has exclusive rights to the
new technology. While the PCR method rapidly duplicates DNA, the new
method uses an enzyme called Q-beta replicase to trigger RNA replication.
A gene spliced into the RNA acts as a probe to seek out a matching gene.
To detect HIV, a gene from the virus would be spliced into the RNA, and
would bind to the matching gene on any HIV. Fred R. Kramer, PAUl M.
Lizardi, and their colleagues, then at Columbia University, discovered
the unique enzyme.