Visible Genetics Inc.

                             For Immediate Release

Contacts:                                           Bruno Maruzzo (416)813-3271
David Sassoon (212)527-7453                               Visable Genetics Inc.
Rowland-Wang Healthcare                                       
Roanne Argyle (416)968-7311
Argyle Rowland Worldwide

     Visible Genetics Inc. Receives FDA Allowance For HIV Genotyping Trials

             - Significant milestone for VGI's genotyping products -

TORONTO, CANADA (December 24, 1998) Visible Genetics Inc. (NASDAQ: VGIN) today
announced that it has been allowed by the U.S. Food and Drug Administration
(FDA) to initiate human clinical studies of its OpenGene(TM) HIV Genotyping
system under its Investigational Device Exemption (IDE) application. As a result
of the FDA's decision, a multi-site series of validation and proficiency trials
for VGI's OpenGene HIV system will begin immediately. A pivotal, multi-site
clinical trial known as SEARCH I will begin early in January. This study will be
the keystone of the Pre-Market Approval (PMA) application. In addition, five
other U.S. trials using previously collected and banked specimens sponsored by
independent investigators will be supported by this IDE and VGI OpenGene
systems.

The VGI OpenGene system that will be used under the IDE include three major
components:

1.   The MicroGene Clipper(TM): a clinical DNA sequencer designed for genotypic
     applications. The sequencer has been optimized for rapid, accurate and
     reproducible results combined with high sensitivity and minimal labor
     requirement for genotypic applications. The sequencer can do a genotypic
     analysis of the gag/pol region of HIV in less than 30 minutes, as compared
     to research sequencers that may take from two to six hours.

2.   The GeneObjects(TM) Clinical Management System: an integrated software
     package that provides control of the Clipper, performs analysis of the
     data, checks for contamination, and features full error detection and error
     correction of the DNA sequence. The package is capable of going from raw
     sequence data to a full resistance report in less than fifteen minutes.

3.   The HIV TruGene(TM) Kit: an integrated chemistry kit that contains a
     protocol, all reagents (approximately 20 components), and controls needed
     to produce the material from the HIV in the AIDS patient's blood to final
     sequence output on the Clipper. The kit makes use of CLIP, VGI's patented
     method that provides full 3',5' sequence at reduced costs, and helps
     optimizes error correction and detection.



The VGI OpenGene system is designed to detect mutations in the genes of HIV in
the blood of AIDS patients. These mutations are known to cause the HIV virus to
be resistant to current drug therapy. By knowing the HIV mutation pattern in
each patient, a physician may optimize drug selection. OpenGene systems are now
in use for research applications in Europe and the US, and VGI has shipped
significant numbers of European HIV TruGene Kits this quarter.

"This is an important milestone for the Company and, is to our knowledge the
first IDE allowed by the FDA for any genotyping product," said John K. Stevens,
C.E.O. of Visible Genetics. "We have worked hard to meet the Current Good
Manufacturing Practice Standards (cGMP) requirements set by the FDA for our
kits, instruments and software. Genotyping, particularly HIV genotyping, is new
territory for everyone, and we have had positive and strong support from the FDA
in designing the necessary protocols and approaches to demonstrate clinical
utility of this new method as well as validation of our system. This IDE
allowance is the first important step to obtaining full PMA clearance in the
U.S. "

SEARCH I will be a US-based prospective trial that will use about 20 AIDS
physicians. Two groups of patients will be enrolled: Group 1 will be
retrospectively genotyped, and the results will not be available to the
physician, while Group 2 will be prospectively genotyped and the results will be
used by the physician to actually select drugs in an effort to maximally depress
the virus based on the HIV drug resistance profile produced by the OpenGene
System.

The SEARCH I design is similar to the VGI sponsored French VIRADAPT study,
presented Nov 12th 1998 at the 4th International Congress on Drug Therapy in HIV
Infection in Glasgow. The VIRADAPT results showed statistically significant
reduction of about 0.5 log units in viral levels in the genotypic arm at both
three month and six month analysis points. In addition, preliminary economic
analysis of the VIRADAPT data showed that each dollar spent on genotyping saved
approximately $3.83 in non-drug based costs.

Visible Genetics Inc. manufactures and markets high performance automated DNA
sequencing systems and complete kits for the analysis of genes linked to
disease. The Company's OpenGene(TM) system employs proprietary stratified DNA
testing and single-tube, single-step sequencing methods to significantly reduce
the time and cost involved in identifying clinically relevant genetic
information. VGI is a leader in the emerging field of pharmacogenomics, which
will use genetic information in the identification, and analysis of genes in
order to improve patient care and reduce healthcare costs.

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