Searching for genetic connections

Dr. Olga Kovalchuk, a biological sciences researcher at the University of Lethbridge, has received a significant award from the Canadian Breast Cancer Foundation – Prairies/NWT Region Research Grant program to study how something as simple as sleep disruption could make cells vulnerable to cancer.

"The disruption of circadian rhythms (a sleep-wake cycle) due to shift work or exposure to light at night has recently been suggested as a breast carcinogen, as elevated rates of breast cancer have been reported in groups of shift workers in countries all over the world, including Canada," says Kovalchuk.

Dr. Olga Kovalchuk is one of the country's leading epigenetic researchers.

Circadian rhythms are the equivalent of a person's internal clock, and help govern such things as sleep patterns, alertness and other factors. Circadian rhythms are found in most living things, from bacteria to plants and animals.

They follow a set pattern that, if shifted around, cause a number of biological processes to change, and not always for the better – as any sleep-deprived new parent or shift worker adjusting to a new schedule can attest.

To tease out the minute changes in the genetic markers that make up the road map to solving this challenge, Kovalchuk will employ epigenetics – the study of how an individual gene can go wrong or not work properly over a person's lifetime.

"The precise mechanisms of breast cancer induced by circadian rhythm disruption are elusive," says Kovalchuk, a professor and Board of Governors' Research Chair, CIHR Chair in Gender and Health. "In recent years, the role of epigenetic changes as a cause of breast cancer has been increasingly recognized, so we are going to attack this challenge from that perspective."

Epigenetics is the study of how individual genes and components of individual genes can change in response to environmental conditions or other factors.

In addition to the hard-wired traits in DNA, epigenetic changes can occur in response to a change in lifestyle or other trigger, and can be passed from one generation to another.

With colleague and neuroscientist Dr. Robert Macdonald at the Canadian Centre for Behavioural Neuroscience, Kovalchuk and their respective lab teams will develop a model to test how changes in genetic structure are brought about by sleep or circadian disruption. They will also look at how those epigenetic changes affect cells, which in turn would make them a target for cancer.

The group will study mammary glands and look at the genetic switches that are turned on or off in response to the circadian pattern changes.

Kovalchuk will receive $125,000 per year for three years. Her award is part of a 19-project, $6.8 million announcement made in early November by the Canadian Breast Cancer Foundation – Prairies/NWT Region. The CBCF supports research projects that demonstrate high degrees of innovation or novelty in breast cancer research.