FOR IMMEDIATE RELEASE

March 2, 2011

Researchers discover new roles for genes involved in basic cell function

An international scientific collaboration has led to the discovery of a new role for three genes that influence our cells’ ability to duplicate DNA, and may help improve our understanding of many disorders such as foetal and childhood growth retardation, abnormal development of body parts and cancer.

The discovery, published in the February 27th online edition of Nature Genetics, was part of the Atlantic Medical Genetic and Genomic Initiative (AMGGI), a Genome Atlantic-led project that researches the molecular causes of rare or ‘orphan’ genetic diseases. In this case, scientists at Dalhousie University were looking for the genetic basis of Meier-Gorlin Syndrome (MGS), a rare condition that features short stature, small ears and undeveloped kneecaps. Researchers identified mutations in three genes known to play a key biological role.

“This is the first time anyone has identified mutations in this set of important regulatory genes in any mammal,” says Dr. Mark Samuels, project co-lead. “It’s a great example of the value of this type of research where we learn the cause of a disease, and discover things about our cellular function that we didn’t know before.”

Samuels went on to explain that having a probable molecular diagnosis can improve MGS patient management as physicians will have a better documented history of what to expect from the disorder. As well, genetic counselors can provide more accurate information for family planning.

“It’s important to note that behind the science and the statistics, there are real people suffering. It’s an immense relief for patients,” says Samuels.

The discovery also highlights the importance of research on the ‘orphan’ diseases, which affect few individuals per disease, but collectively, impact a large part of the population, and use a significant amount of health care resources. Research suggests that up to 70% of admissions to paediatric hospitals may be related to some kind of genetic disorder.

The discovery will also be of broader scientific interest because of its implications in cell growth. For normal cell division, there is a highly controlled DNA duplication process that ensures that only two copies of each chromosome are created. More or fewer copies can lead to abnormal cell development. Accelerated cell division is often associated with cancer. The three genes, named ORC1L, ORC4L and CDT1, play a role in this important function.

According to Dr. David Skidmore, lead clinical researcher on the MGS project at the IWK Health Centre and an assistant professor of pediatrics at Dalhousie Medical School, “We were aware that many of the reported cases of MGS occurred in individuals of Acadian or Cajun descent. This led us to suspect that these individuals may  have inherited MGS from a common ancestor who lived in Nova Scotia prior to the expulsion of the Acadians in the 18^th century.”

To find the causal genes, researchers compared genetic mapping data of MGS cases from Atlantic Canada, Quebec and Louisiana.

“Patients in Canada found it very interesting to realize they share a family history with their likely very distant cousins,” says Samuels.

Along with Drs. Samuels and Skidmore, collaborators on this finding included Dr. Duane Guernsey of Dalhousie University, Drs. Jacques Michaud and Cheri Deal at the University of Montreal, and Drs. Duane Superneau and Sylvie Langlois in Louisiana and British Columbia.

In an unusual coincidence, European researchers working independently also submitted findings about these three genes to Nature Genetics, which are included in the same issue of the publication, giving even more scientific merit to the discovery.

The AMGGI project is funded in part by the Government of Canada via Genome Canada and Genome Atlantic, as well as a large number of organizations, including the Atlantic Canada Opportunities Agency – Atlantic Innovation Fund, Dalhousie University, Capital Health and the IWK Foundation. The full list can be found on our website.

-30-

Sue Coueslan

Director of Communications and Government Relations, Genome Atlantic

902.222.3178; sue@genomeatlantic.ca; www.genomeatlantic.ca

About the Atlantic Medical Genetics and Genomics Initiative

The Atlantic Medical Genetics and Genomics Initiative is a $9.2M, multi-partner, multi-institution research project designed to find the genetic cause of nearly 30 monogenic diseases in Atlantic Canada. Leveraging the expertise of a wide range of medical and research professionals from medicine to genetics and genomics to ethics, the project aims to integrate gene research into clinical practice for advanced knowledge and improved health care.

The project is funded in part by the Government of Canada via Genome Canada/Genome Atlantic, Capital Health, IWK Health Centre, Dalhousie University, Nova Scotia Research and Innovation Trust, Dalhousie Medical Research Foundation, Nova Scotia Health Research Foundation, ACOA-AIF, and others as listed on our website.

About Genome Atlantic

Genome Atlantic is a not-for-profit organization that was formed in 2000 with a mission to develop and lead a program of genomics research that delivers tangible economic, social and environmental benefits to Atlantic Canada.

In its first ten years, Genome Atlantic has partnered with government, academic, industry and research institutions to enable ten projects totaling $68 million, ranging from agriculture and forestry, to aquaculture and human health. It is one of six genome centres across the country, under the umbrella of Genome Canada.