Same Drug, Different Results: MUHC Researcher on the Path to Personalized Medicine
News Jun 27, 2008
Medicine has moved a little bit closer to the era of tailor-made treatments, based on the genetic profiles of individual patients, according to recent research conducted by Dr Rima Rozen of the Research Institute of the McGill University Health Centre (RI MUHC) at the Montreal Children's Hospital and McGill University. Her study, published June 18 in the journal Pharmacogenetics and Genomics, shows how minor genetic differences between individuals alter the way a common drug affects the body.
Rozen has measured the impact of Methotrexate - a drug that inhibits the metabolism of folate - on mice with an altered MTHFR gene, which is a gene crucial for folate metabolism.
The results were striking: after treatment with Methotrexate, mice with the altered gene had approximately 20 per cent less hemoglobin and red blood cells than their counterparts with non-altered genes. The altered mice also showed increased susceptibility to liver and kidney damage following treatment.
"We know that these results are applicable to humans because a parallel mutation in the human MTHFR gene affects human folate metabolism similarly. The results demonstrate that medication affects subjects differently according to individual genetic traits," Dr. Rozen explained. "And tests exist to detect this mutation."
Genetic testing would allow physicians the modify treatment based on each patient's personal genetic makeup, limiting potential side effects.
In earlier studies, Rozen's laboratory cloned the MTHFR gene and identified the common variant which interferes in folate metabolism in human populations. Between 10 and 15 per cent of the total caucasian population have two copies of the variant in MTHFR.
Folate, a form of water-soluble Vitamin B2, is essential to the production of red blood cells and provides protection against spina bifida, other birth defects, and heart disease. Patients with cancer or auto-immune diseases are often treated with medications that affect folate metabolism, but physicians are not trained to verify how patients naturally metabolize folate, even though this could be an important factor in effective treatment.
"This is a first step towards personalized medicine that is based not only on symptoms but also on the patient's own genetic 'baggage,'" Rozen said. "This trend definitely represents the medicine of the future."
Dr. Rima Rozen is a Scientist in the Medical Genetics and Genomics Axis of the RI MUHC at the Montreal Children's Hospital. At McGill University, she holds the positions of Associate Vice-Principal (Research and International Relations) and Professor in the Human Genetics, Pediatrics and Biology Departments.
Researchers Awarded $28M for Illuminating Druggable Genome NIH GrantsNews
Researchers receive grants as part of the NIH program focused on experimental and informatics approaches to characterize understudied proteins from three gene families: ion channels, G protein-coupled receptors (GPCRs), and protein kinases.READ MORE
No Country for Old GenesNews
Our modern world is radically different from the one we evolved in, and that creates a mismatch between the environment our genes were evolved to face, and the world those genes now encounter. A new review looks at how certain genes that benefited humans in our genetic past now predispose us to disease in old age.READ MORE
CRISPR Editing Stops HIV Virus in Infected CellsNews
Human immunodeficiency virus-1 (HIV-1) infection is a chronic disease affecting more than 35 million people worldwide. The infection can be controlled by antiretroviral therapy (ART), but there is still no complete cure. Now, a new study targeting the regulatory genes of the virus using CRISPR/Cas9 has helped block the production of the virus by infected cells.READ MORE