Double mutants of dihydrofolate reductase and methods of using same

US6642043B1 · kind B1 · utility

Assignee

• Sloan Kettering Institute for Cancer Research · US

Inventors

• Joseph R. Bertino · Branford, US
• Emine A. Ercikan-Abali · New York, US
• Debabrata Banerjee · Floral Park, US
• Shin MINEISHI · New York, US
• Michel Sadelain · New York, US

Key dates

• Filing date: Jan 20, 1999
• Grant date: Nov 4, 2003
• Expiry date: Jan 20, 2019

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C12N15/65
• WIPO field: Biotechnology
• WIPO sector: Chemistry

Abstract

New mutant forms of human dihydrofolate reductase (DHFR) which have properties superior to the previously disclosed mutants have mutations at both amino acid 22 and amino acid 31. Specific mutant forms are Ser31Tyr22, Ser31Phe22, Gly31Tyr22, Gly31Phe22, Ala31Tyr22 and Ala31Phe22. The mutant DHFR of the invention maybe used as a selectable marker, and to modify the genome of human cells, particularly bone marrow cells or peripheral blood stem cells, to render them resistant to chemotherapy using antifolate agents.