EXHIBIT 5.1

January 16, 2002

Visible Genetics Inc.
Suite 1000, Box 333
700 Bay Street
Toronto, Ontario
Canada M5G 1Z6

Gentlemen:

VISIBLE GENETICS INC.
REGISTRATION STATEMENT ON FORM F-3

    We have acted as Canadian counsel to Visible Genetics Inc. (the "Company")
in connection with the filing with the Securities and Exchange Commission of the
Company's Registration Statement on Form F-3 (the "Registration Statement")
under the Securities Act of 1933, as amended (the "Securities Act") relating to
the registration of (the "Offering") 2,637,890 common shares (the "Common
Shares"), to be sold by the Selling Shareholders. Capitalized terms used herein
but not otherwise defined shall have the respective meanings set forth in the
Registration Statement.

    For the purposes of expressing the opinion set forth herein, we have
examined originals or copies, certified or otherwise identified to our
satisfaction, of the articles of incorporation and the by-laws of the Company,
each as amended from time to time, and resolutions of the directors of the
Company with respect to the matters referred to herein. We have also examined
such certificates of public officials, officers of the Company, corporate
records and other documents as we have deemed relevant or necessary as a basis
for the opinion expressed below. In our examination of such documents, we have
assumed the authenticity of all documents submitted to us as certified copies or
facsimiles thereof.

    We are barristers and solicitors qualified to practice law in the Province
of Ontario and our opinion expressed below is limited to the laws of such
Province and the laws of Canada applicable therein and should not be relied
upon, nor is it given, in respect of the laws of any other jurisdiction.

    Based upon and subject to the foregoing, we are of the opinion that the
Common Shares have been duly authorized and are validly issued, fully paid and
non-assessable shares of the Company.

    We hereby consent to the use of this opinion as an exhibit to the
Registration Statement and to the use of our name under the caption "Legal
Matters" in the Prospectus forming a part of the Registration Statement. We
hereby also consent to the incorporation by reference of this consent into a
subsequent registration statement filed by the Company pursuant to Rule 462(b)
under the Securities Act relating to the offering covered by the Registration
Statement. In giving such consent, we do not thereby concede that we are in the
category of persons whose consent is required under Section 7 of the Securities
Act or the rules and regulations promulgated thereunder, or that we are
"experts" within the meaning of the Securities Act or the rules and regulations
promulgated thereunder.

Yours very truly,
/s/ OSLER, HOSKIN & HARCOURT LLP