Anne Bassett

Senior Scientist, Toronto General Hospital Research Institute (TGHRI)
Keywords: genetics, 22q11.2 deletion syndrome, congenital heart defect, developmental disorders, schizophrenia

Our research is forging new paths of discovery in finding the multiple genetic causes of complex developmental disorders like congenital heart disease and schizophrenia. Through our ground-breaking work we are helping to develop a better understanding of emerging rare disorders caused by clinically relevant genetic changes. The most prominent of these involve changes in the structure of the human genome that affect early development and risk of diseases arising later in life. We are world leaders in the study of adults with the most common genomic disorder - 22q11.2 Deletion Syndrome. This complex multisystem condition causes a significant proportion of major congenital heart disease and schizophrenia in the general population. Using the latest genetic techniques, including genome sequencing, and clinical assessments, our research is leading to more specific molecular diagnostics and to delineation of disease pathways. A novel example is our finding of a new pathway for tetralogy of Fallot, a major congenital heart disease (“blue babies”). The ultimate goal of our research program is to use this new knowledge to develop innovative management and preventive strategies to improve outcomes for these complex lifelong conditions.

Barriers to healthcare access for adults with 22q11.2 deletion syndrome

Study Status: Active
Study Purpose: We plan to survey adults with a genetic condition called 22q11.2 deletion syndrome (“22q”) and their caregivers about their health and health care experiences. We aim to update the questionnaire that was given 10 years ago.
Background: 1 in every 2148 babies is born with a piece missing from chromosome 22. This means that there is a loss of several genes that normally direct how the body forms and functions. This genetic condition is called 22q11.2 deletion syndrome (“22q”). 22q affects many body systems early on in development and later in life.  Common features include birth defects of the heart and palate, learning disabilities, low calcium levels, curvatures of the spine, seizures, anxiety, schizophrenia, and many more.  Most people with 22q need care from many specialists.  Ten years ago, we gave a questionnaire to adults 22q and their caregivers.  The questionnaire asked about the health burden of 22q and the services they had received. We published the results. At that time, many of the people who completed the questionnaire noted the lack of medical and social services for adults with 22q. They especially noted this at the time of transition from pediatric to adult care.  They also noted a high burden of illness, and said that mental health problems were the most challenging.
Study Methods: We aim to update the questionnaire given 10 years ago, to examine:   1. Current health and other burdens and challenges they face;  2. Current access to medical and social services and transition to adult care;  3. Whether they believe that attending the Toronto General Hospital’s Dalglish Family 22q Clinic, our world-leading multidisciplinary clinic for adults with 22q, has improved their care, and how this care compares to care received elsewhere  4. Barriers they face when attending appointments in person, and with online/virtual services The answers will be crucial for planning purposes and for further improving the care we provide at our clinic. Results will also provide a snapshot (post-pandemic) that will be of value to others around the world who are interested in developing a similar clinic for individuals with 22q and their families
Health Conditions: Genetics

 

Adult-onset obstructive sleep apnea in 22q11.2 deletion syndrome

Study Status: Completed
Study Purpose: Sleep apnea is a treatable sleep disorder that can affects how well the brain and heart work, usually in older people. We studied how common sleep apnea is in young adults with a genetic condition who have other health issues.
Background: 1 in every 2148 babies babies is born with a piece missing from chromosome 22. This genetic condition is called 22q11.2 deletion syndrome (“22q”). 22q affects many body systems early on in development and later in life.  We have discovered that one of those later 22q health problems is a sleep disorder called obstructive sleep apnea (OSA).  When a person has OSA, the muscles in the back of the throat become too relaxed during sleep and can block off breathing.  Because of the low oxygen levels, the brain wakes the person up, every once in a while, to breathe again. This leads to very broken sleep and can also increase the risk of other health problems such as high blood pressure and heart disease.  OSA is a treatable condition.
Study Methods: We reviewed the medical records of adults with 22q to study OSA.
Key Findings: We found that about 1 in 10 people with 22q had OSA. In addition to having 22q, obesity, older age, asthma, and being born male increased the risk for OSA in 22q, just as they do in the general population. We also found something new that is important for people with 22q. Adults with 22q who had certain types of surgery to correct the structure of their palate (roof of the mouth) when they were children were at a higher risk of developing OSA years later. It is common for children with 22q to undergo surgery to correct the structure of the roof of their mouth to improve their ability to swallow and to speak.  Our results show that people with a history of this surgery may need to be assessed and treated for OSA many years after the surgery.  Also, using other surgical techniques in childhood may help reduce this risk. Importantly, we found that adults with 22q could be successfully treated for the OSA with standard care. This included being able to use a CPAP (continuous positive airway pressure) machine.
Health Conditions: Genetics,Lungs & Breathing conditions

 

For a list of Dr. Bassett's publications, please visit PubMed or Scopus.
Senior Scientist, Toronto General Hospital Research Institute (TGHRI)

Canada Research Chair in Schizophrenia Genetics and Genomic Disorders (Tier 1)
Professor, Department of Psychiatry, University of Toronto
Director, Clinical Genetics Research Program, Centre for Addiction and Mental Health
Full Member, Institute of Medical Science, Faculty of Medicine (graduate studies), University of Toronto
Member, University of Toronto Neuroscience Program