26 Novel Genes Linked to Intellectual Disabilities

Author: Centre for Addiction and Mental Health
Published: 2017/04/16 - Updated: 2025/01/22
Publication Details: Peer-Reviewed, Research, Study, Analysis
Topic: Personalized Medicine - Publications List

Page Content: Synopsis - Introduction - Main - Insights, Updates

Synopsis: The article highlights a groundbreaking study identifying 26 novel genes linked to intellectual disability, a condition often co-occurring with autism spectrum disorders. It offers insights into the genetic underpinnings of these conditions, suggesting potential for personalized medicine in diagnosis and treatment. This research not only enriches our understanding of brain development but also provides tools for genetic screening and counseling, particularly in populations with a history of consanguinity, paving the way for more effective, tailored healthcare - Disabled World (DW).

Introduction

Researchers at the Centre for Addiction and Mental Health (CAMH) and Queen's University have identified 26 new genes linked to intellectual disability. Currently most patients with intellectual disability receive no molecular diagnosis, which significantly affects their health and shortens their lifespan.

Focus

The study, published online today in Molecular Psychiatry, has implications for the diagnosis and clinical care of those affected, and also adds to our growing knowledge of brain development and functioning. It may eventually lead to personalized treatments for affected individuals. Interestingly, some of the genes identified are thought to be connected with autism spectrum disorders.

"This is the largest study of its kind on intellectual disability to come out of North America," said Dr. John Vincent, team leader and Senior Scientist who heads the MiND (Molecular Neuropsychiatry and Development) Laboratory in the Campbell Family Mental Health Research Institute at CAMH. The study was jointly led with Prof. Muhammad Ayub of Queen's University.

More than one in 100 children worldwide are affected by intellectual disability, which is characterized by significant limitations in learning that also affect their day-to-day lives. Frequently, intellectual disability also accompanies symptoms of autism spectrum disorders, and many genes have been found to be shared by the two illnesses.

The study involved 192 families from Pakistan and Iran with more than one affected family member. Intellectual disability is frequently caused by recessive genes, meaning that an affected child gets a defective copy of the gene from each parent.

The families in the study all had a history of marriage among relatives, which occurs quite commonly in communities in South Asia, the Middle East and Africa. Studying families with this background, and multiple affected individuals, can enable researchers to identify disease genes that would otherwise remain hidden.

The Canadian research team pinpointed mutations related to intellectual disability in half of these 192 families, in 72 different genes. The identification of 26 new genes adds to 11 new genes that the team had previously linked to intellectual disability.

Implications for diagnosis and care

One immediate implication of the study is to prevent future cases of intellectual disability, the researchers note. Unaffected family members and relatives could be genetically screened to see if they carry these mutations, and provided with counselling on the risks of "within family" marriages.

A broader goal is to develop diagnostic screening tools that are also relevant to populations in which "within family" marriages are rare, such as Canada, USA, Japan, China and Europe. Ultimately, this information would be used to plan more personalized treatment.

While 26 genes may seem a substantial number, there are likely hundreds of genes that, when defective, may lead to intellectual disability. "The strategy we have used speeds up the process of identifying disease genes and of enabling diagnostic labs to deliver more accurate information for clinicians and families," says Dr. Vincent. This strategy involves various genetic techniques, including microarray genotyping and whole exome sequencing, and studying families with a history of marriage among relatives.

"There's an opportunity now to further explore the functioning and biological pathways of these genes, and to help complete the picture of how the central nervous system works," says Dr. Vincent. "Knowing the genes involved is a big step forward, but understanding how they function is also crucial before we can start planning treatments or even cures."

Centre for Addiction and Mental Health (CAMH)

The Centre for Addiction and Mental Health (CAMH) is Canada's largest mental health and addiction teaching hospital and a world-leading research centre in this field. CAMH combines clinical care, research, education, policy development and health promotion to help transform the lives of people affected by mental illness and addiction. CAMH is fully affiliated with the University of Toronto, and is a Pan American Health Organization/World Health Organization Collaborating Centre.

Insights, Analysis, and Developments

The exploration of genetic factors underlying intellectual disability, as outlined in this article at Disabled World (DW), serves as a critical reminder of the complex interplay between genetics and human cognition. We gain not only a deeper understanding of the myriad genes and mutations associated with intellectual disability but also pave the way for more personalized and effective diagnostic, intervention, and treatment strategies. This resource offers hope and direction in an area where understanding has historically been limited. The continuous updating and detailed annotation of such databases underscore the importance of genetic research in enhancing the lives of those affected, ensuring they receive the support and opportunities they deserve. This work exemplifies the profound impact that genetic science can have on improving quality of life and underscores the necessity for ongoing research and community engagement in this field

Attribution/Source(s): This peer reviewed publication was selected for publishing by the editors of Disabled World (DW) due to its relevance to the disability community. Originally authored by Centre for Addiction and Mental Health and published on 2017/04/16, this content may have been edited for style, clarity, or brevity. For further details or clarifications, Centre for Addiction and Mental Health can be contacted at camh.ca NOTE: Disabled World does not provide any warranties or endorsements related to this article.