[LETTERHEAD OF VISIBLE GENETICS INC.]
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                              For Immediate Release

Contacts:
Bruno Maruzzo                                   David Sassoon (212)527-7453
Visible Genetics Inc.   (416) 813-3271                Rowland-Wang Healthcare

Antonio Ferrer                                  Roanne Argyle (416)968-7311
Roche Diagnostics Spain (+34 933067100)               Argyle Rowland Worldwide

 VISIBLE GENETICS INC. AND ROCHE DIAGNOSTICS S.L. ENTER EXCLUSIVE DISTRIBUTION
         AND MARKETING AGREEMENT FOR VGI PRODUCTS IN SPAIN AND PORTUGAL

TORONTO, CANADA, April 16, 1999 - Visible Genetics Inc. (VGI, Nasdaq:VGIN) and
Roche Diagnostics S.L. (Roche) have entered into an agreement whereby Roche will
be the exclusive distributor in Spain and Portugal of VGI's OpenGene(TM)
automated DNA sequencing system and GeneKits(TM), including HIV-1, Hep C, Hep B,
and TB TruGene(TM) assays in the diagnostics market. The agreement is for a
period of three years and has provisions that guarantee minimum annual revenues
over that period to VGI.

"This agreement represents an important milestone for VGI and is the first of
many in our worldwide strategy of working with the best healthcare partner in
each geographical market. Overnight, we have placed in the field, a talented,
high-energy team of approximately 200 experts selling, marketing and supporting
VGI products. In addition, the Roche team will help bring VGI's products to
early commercialization by working with VGI on the extensive clinical trial
program we already have in place in Europe," comments Dr. Chalom Sayada, Vice
President Europe for Visible Genetics. "For example, their involvement in our
VIRADAPT, VIGILANCE I, and VIGILANCE II studies will help focus the use of
genotyping in the reduction of HIV-1 infection and help improve the management
of this terrible disease," Dr. Sayada continued.


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"We believe this collaboration allows us to offer a complete solution to the
physician for the diagnosis and monitoring of their infectious disease patients,
particularly those patients suffering with the HIV-1 and hepatitis viruses,"
says Joachim Langer, General Manager of Roche Diagnostics Spain. "We believe
that this complementary product offering will bring added value to our
customers. For example, Roche can now provide doctors with the immunochemistry
tests to detect and confirm the presence of the HIV-1 virus; quantitate the
amount of virus ("viral load") in a patient's blood via PCR (polymerase chain
reaction technology) testing; and then sequence the resistant HIV-1 mutations a
patient has in order to better predict the effectiveness of their antiviral drug
therapy," he added.

Visible Genetics Inc. manufactures and markets high performance automated DNA
sequencing systems and complete diagnostic 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 that uses
genetic information to identify, analyze and treat medical conditions for the
benefit of improving patient care and reducing healthcare costs.

Roche, headquartered in Basel, Switzerland, is a world leader in research-based
healthcare, with principal business in pharmaceuticals, diagnostics, vitamins,
and fragrances and flavours. The Roche Group owns three manufacturing plants in
Spain; one for pharmaceutical products in Leganes (Madrid), another for vitamins
in San Fernando de Henares (Madrid), and a third one in fragrances and flavours
in Sant Celoni. In Spain, there are approximately 2,000 employees, and the total
invoicing in 1998 amounted to 80,000 million Pesetas.

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