U of T research

With more than 80 per cent of Canada’s population living in cities and globally more people move into urban locales, there is an urgent need to learn how to design and modify cities to improve – not degrade – public health.

So �ؿ�ζSM researchers have established the Canadian Urban Environmental Health Research Consortium (CANUE), made up of more than 80 environmental health experts in academia, government, NGOs and the private sector, who will work together on an urban health research program to improve understanding of how cities can evolve to optimize health.

“This consortium will provide critical environmental health research so policy-makers and urban and regional planners can make evidence-based decisions when addressing the challenges of urbanization and growing suburbs,” said Jeffrey Brook, assistant professor of Occupational and Environmental Health at U of T's Dalla Lana School of Public Health and CANUE lead. “Climate change and how it impacts cities and residents is another priority for CANUE.”

On May 18, Brook’s research team received funding from the Canadian Institutes of Health Research to examine issues such as sprawl, traffic congestion, car-dependency, social equity and sustainability.

The research team will link standardized environmental exposure data about air quality, green space, walkability, noise, weather/climate and other aspects of the urban/suburban environment to existing human health data platforms, including the Canadian Partnership for Tomorrow Project.

U of T researchers receive $1.76 million to tackle Indigenous tobacco use, lung cancer

ullahnor — Tue, 27 Sep 2016 15:49:17 +0000

U of T researchers receive $1.76 million to tackle Indigenous tobacco use, lung cancer

ullahnor Tue, 09/27/2016 - 11:49

Cutline

U of T Professor Robert Schwartz leads a research team to study tobacco use in Canadian Indigenous communities (photo by Jackie Atlas)

Nicole Bodnar

Author legacy

Nicole Bodnar

Topic

Dalla Lana School of Public Health

tobacco

Subheadline

U of T researchers hope to develop a model for reducing commercial tobacco use

A team led by U of T researchers Robert Schwartz and Michael Chaiton has received a $1.76 million grant from the Global Alliance for Chronic Diseases to reduce commercial tobacco use and prevent chronic lung disease in Canadian Indigenous communities.

“Smoking cigarettes is one of the worst things you can do to your health and is a major risk factor for all lung diseases,” said Schwartz, executive director of the Ontario Tobacco Research Unit and professor of public health policy at U of T's Dalla Lana School of Public Health.

Through the study, researchers will collaborate with 13 Indigenous communities to support the development of culturally appropriate tobacco interventions to reflect socioeconomic, cultural and political influences.

About 18 per cent of Canadians smoke cigarettes, but in the First Nations, Inuit and Métis populations, the rates are 35.8 per cent, 59.8 per cent and 33 per cent respectively. The high rates of commercial tobacco use in Indigenous populations have led to a variety of health issues, lower life expectancy than the general Canadian population and higher rates of tobacco-related death.

“Working together with communities, we hope the study will help close the very large gap in the relative health burden experienced by Aboriginal as compared to non-Aboriginal people in Canada,” said Schwartz, who is also a senior scientist at the Centre for Addiction and Mental Health.

Landmark Map Reveals the Genetic Wiring of Cellular Life

ullahnor — Thu, 22 Sep 2016 20:49:46 +0000

Landmark Map Reveals the Genetic Wiring of Cellular Life

ullahnor Thu, 09/22/2016 - 16:49

Jovana Drinjakovic

Author legacy

Jovana Drinjakovic

Topic

Breaking Research

Research & Innovation

Subheadline

The new map breaks away from the old way of studying genes one at a time, showing how genes interact in groups to shed light on the genetic roots of diseases.

Researchers at the �ؿ�ζSM’s Donnelly Centre have created the first map that shows the global genetic interaction network of a cell. It begins to explain how thousands of genes coordinate with one another to orchestrate cellular life.

The study was led by U of T Professors Brenda Andrews and Charles Boone, and Professor Chad Myers of the University of Minnesota-Twin Cities. It opens the door to a new way of exploring how genes contribute to disease with a potential for developing finely-tuned therapies. The findings are published in the journal Science.

“We’ve created a reference guide for how to chart genetic interactions in a cell," said Michael Costanzo, a research associate in the Boone lab and one of the researchers who spearheaded the study. "We can now tell what kind of properties to look for in searching for highly connected genes in human genetic networks with the potential to impact genetic diseases."

The study took 15 years to complete and adds to Andrews’ rich scientific legacy for which she was awarded a Companion of the Order of Canada.

Read more about their work

Over a decade ago, an international consortium of scientists first deleted every yeast gene, one by one. They were surprised to find that only one in five were essential for survival. It wasn’t until last year that advances in gene-editing technology allowed scientists to tackle the equivalent question in human cells. It revealed the same answer: a mere fraction of genes are essential in human cells too.

These findings suggested most genes are “buffered” to protect the cell from mutations and environmental stresses. To understand how this buffering works, scientists had to ask if cells can survive upon losing more than one gene at a time, and they had to test millions of gene pairs.

Andrews, Boone and Myers led the pioneering work in yeast cells by deleting two genes at a time in pair combinations. They were trying to look for gene pairs that are essential for survival. This called for custom-built robots and a state-of-the-art automated pipeline to analyse almost all of the mind-blowing 18 million different combinations.

The yeast map identified genes that work together in a cell. It shows how, if a gene function is lost, there’s another gene in the genome to fill its role. Consider a bicycle analogy: a wheel is akin to an essential gene – without it, you couldn’t ride the bike. But front brakes? Well, as long as the back brakes are working, you might be able to get by. But if you were to lose both sets of brakes, you are heading for trouble.

Geneticists say that front and back brakes are “synthetic lethal,” meaning that losing both – but not one – spells doom. Synthetic lethal gene pairs are relatively rare, but because they tend to control the same process in the cell, they reveal important information about genes we don’t know much about. For example, scientists can predict what an unexplored gene does in the cell simply based on its genetic interaction patterns.

It’s becoming increasingly clear that human genes also have one or more functional backups. So researchers believe that instead of searching for single genes underlying diseases, we should be looking for gene pairs. That is a huge challenge because it means examining about 200 million possible gene pairs in the human genome for association with a disease.

Fortunately, with the know-how from the yeast map, researchers can now begin to map genetic interactions in human cells and even expand it to different cell types. Together with whole-genome sequences and health parameters measured by new personal devices, it should finally become possible to find combinations of genes that underlie human physiology and disease.

“Without our many years of genetic network analysis with yeast, you wouldn’t have known the extent to which genetic interactions drive cellular life or how to begin mapping a global genetic network in human cells," said Boone, who is also a professor in U of T’s molecular genetics department and a co-director of the Genetic Networks program at the Canadian Institute for Advanced Research (CIFAR) and holds Canada Research Chair in Proteomics, Bioinformatics and Functional Genomics. We have tested the method to completion in a model system to provide the proof of principle for how to approach this problem in human cells. There’s no doubt it will work and generate a wealth of new information.”

The concept of synthetic lethality is already changing cancer treatment because of its potential to identify drug targets that exist only in tumour cells. Cancer cells differ from normal cells in that they have scrambled genomes littered with mutations. They’re like a bicycle without a set of brakes. If scientists could find the highly vulnerable back-up genes in cancer, they could target specific drugs at them to destroy only the cells that are sick, leaving the healthy ones untouched.

U of T research

U of T researchers establish new consortium studying environmental impacts on public health

Read more about Brook's research

U of T researchers receive $1.76 million to tackle Indigenous tobacco use, lung cancer

Read more about Robert Schwartz's research

Landmark Map Reveals the Genetic Wiring of Cellular Life

Read more about Andrews' and Boone's research

Read more about their work

Read a Vice article about the breakthrough

Read a Motherboard article