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    Last Updated: 01/09/2026

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    MediFind found 44 doctor with experience in RASopathies near Ontario, CA. Of these, 42 are Experienced and 2 are Advanced.

    Location
    LocationClose
    44 providers found
      Advanced in RASopathies

      Susan Zeesman
      Advanced in RASopathies

      Susan Zeesman
      Hamilton, ON, CA 

      Susan Zeesman practices in Hamilton, Canada. Ms. Zeesman is rated as an Advanced expert by MediFind in the treatment of RASopathies. Her top areas of expertise are RASopathies, Cortical Dysplasia, Achalasia Microcephaly Syndrome, and Microcephaly.

      Advanced in RASopathies

      Zeyu L. Yang
      Advanced in RASopathies

      Zeyu L. Yang
      Toronto, ON, CA 

      Zeyu Yang practices in Toronto, Canada. Yang is rated as an Advanced expert by MediFind in the treatment of RASopathies. Their top areas of expertise are Noonan Syndrome, RASopathies, and Obesity.

      Experienced in RASopathies

      Susan I. Blaser
      Experienced in RASopathies

      Susan I. Blaser
      170 Elizabeth Street, 
      Toronto, ON, CA 

      Susan Blaser practices in Toronto, Canada. Ms. Blaser is rated as an Experienced expert by MediFind in the treatment of RASopathies. Her top areas of expertise are Orbital Cellulitis, Oculocerebrocutaneous Syndrome, Cerebelloparenchymal Disorder 3, X-Linked Chondrodysplasia Punctata 2, and Glossectomy.

      Are you looking for a specific type of RASopathies?

      Common conditions include: Cardiofaciocutaneous Syndrome, Cardiomyopathic Lentiginosis, Costello Syndrome, Legius Syndrome, Noonan Syndrome

      Learn about our expert tiers
      Experienced in RASopathies

      David A. Chitayat
      Experienced in RASopathies

      David A. Chitayat

      Mount Sinai Hospital

      ON, CA 

      David Chitayat practices in Canada. Mr. Chitayat is rated as an Experienced expert by MediFind in the treatment of RASopathies. His top areas of expertise are Fetal Akinesia Sequence, Symphalangism Distal, Arthrogryposis Multiplex Congenita, and Congenital Contractures.

      Experienced in RASopathies

      Mary-louise C. Greer
      Experienced in RASopathies

      Mary-louise C. Greer
      555 University Ave, M5G 1X8, 
      Toronto, ON, CA 

      Mary-louise Greer practices in Toronto, Canada. Ms. Greer is rated as an Experienced expert by MediFind in the treatment of RASopathies. Her top areas of expertise are Li-Fraumeni Syndrome, Crohn's Disease, DICER1 Syndrome, Small Bowel Resection, and Endoscopy.

      Experienced in RASopathies

      Brandon S. Sheffield
      Experienced in RASopathies

      Brandon S. Sheffield
      Brampton, ON, CA 

      Brandon Sheffield practices in Brampton, Canada. Mr. Sheffield is rated as an Experienced expert by MediFind in the treatment of RASopathies. His top areas of expertise are Lung Cancer, Non-Small Cell Lung Cancer (NSCLC), Pancreatic Ductal Adenocarcinoma, Costello Syndrome, and Tissue Biopsy.

      Experienced in RASopathies

      Judith E. Allanson
      Experienced in RASopathies

      Judith E. Allanson
      Ottawa, ON, CA 

      Judith Allanson practices in Ottawa, Canada. Ms. Allanson is rated as an Experienced expert by MediFind in the treatment of RASopathies. Her top areas of expertise are Blepharophimosis, Floating-Harbor Syndrome, Cardiofaciocutaneous Syndrome, and Deafness Craniofacial Syndrome.

      Experienced in RASopathies

      Masayoshi Machida
      Experienced in RASopathies

      Masayoshi Machida
      555 University Avenue, M5G 1XB, 
      Toronto, ON, CA 

      Masayoshi Machida practices in Toronto, Canada. Mr. Machida is rated as an Experienced expert by MediFind in the treatment of RASopathies. His top areas of expertise are Scoliosis, Costello Syndrome, Kyphosis, Osteotomy, and Spinal Fusion.

      Experienced in RASopathies

      Kirsten M. Farncombe
      Experienced in RASopathies

      Kirsten M. Farncombe
      Toronto, ON, CA 

      Kirsten Farncombe practices in Toronto, Canada. Ms. Farncombe is rated as an Experienced expert by MediFind in the treatment of RASopathies. Her top areas of expertise are Li-Fraumeni Syndrome, Giant Mammary Hamartoma, Von Hippel-Lindau (VHL) Syndrome, and Noonan Syndrome.

      Experienced in RASopathies

      Mehmet N. Cizmeci
      Experienced in RASopathies

      Mehmet N. Cizmeci
      Toronto, ON, CA 

      Mehmet Cizmeci practices in Toronto, Canada. Mr. Cizmeci is rated as an Experienced expert by MediFind in the treatment of RASopathies. His top areas of expertise are Premature Infant, Intraventricular Hemorrhage of the Newborn, Cerebelloparenchymal Disorder 3, and Hydrocephalus.

      Experienced in RASopathies

      Ebba Alkhunaizi
      Experienced in RASopathies

      Ebba Alkhunaizi
      Toronto, ON, CA 

      Ebba Alkhunaizi practices in Toronto, Canada. Ms. Alkhunaizi is rated as an Experienced expert by MediFind in the treatment of RASopathies. Her top areas of expertise are Fetal Akinesia Sequence, Floating-Harbor Syndrome, Dubowitz Syndrome, and Spondylocostal Dysostosis.

      Experienced in RASopathies

      Oliver A. Kent
      Experienced in RASopathies

      Oliver A. Kent
      101 College Street, M5G 1×5, 
      Toronto, ON, CA 

      Oliver Kent practices in Toronto, Canada. Mr. Kent is rated as an Experienced expert by MediFind in the treatment of RASopathies. His top areas of expertise are Cherubism, Pancreatic Cancer, RASopathies, and Osteitis Fibrosa.

      Experienced in RASopathies

      Anita Villani
      Experienced in RASopathies

      Anita Villani
      Toronto, ON, CA 

      Anita Villani practices in Toronto, Canada. Ms. Villani is rated as an Experienced expert by MediFind in the treatment of RASopathies. Her top areas of expertise are Li-Fraumeni Syndrome, DICER1 Syndrome, Turcot Syndrome, and Carney Complex.

      Experienced in RASopathies

      Robert K. Rottapel
      Experienced in RASopathies

      Robert K. Rottapel
      St Michael's Hospital, 
      Toronto, ON, CA 

      Robert Rottapel practices in Toronto, Canada. Mr. Rottapel is rated as an Experienced expert by MediFind in the treatment of RASopathies. His top areas of expertise are Cherubism, Osteitis Fibrosa, Fibrous Dysplasia, and Ovarian Cancer.

      Experienced in RASopathies

      Jeremy A. Simpson
      Experienced in RASopathies

      Jeremy A. Simpson
      Guelph, ON, CA 

      Jeremy Simpson practices in Guelph, Canada. Mr. Simpson is rated as an Experienced expert by MediFind in the treatment of RASopathies. His top areas of expertise are Cerebral Hypoxia, Heart Attack, Heart Failure, and Becker Muscular Dystrophy.

      Experienced in RASopathies

      Mathew J. Platt
      Experienced in RASopathies

      Mathew J. Platt
      Guelph, ON, CA 

      Mathew Platt practices in Guelph, Canada. Mr. Platt is rated as an Experienced expert by MediFind in the treatment of RASopathies. His top areas of expertise are Heart Attack, Heart Failure, Noonan Syndrome, and Hypertension.

      Experienced in RASopathies

      Brian Raught
      Experienced in RASopathies

      Brian Raught
      Toronto, ON, CA 

      Brian Raught practices in Toronto, Canada. Mr. Raught is rated as an Experienced expert by MediFind in the treatment of RASopathies. His top areas of expertise are Acute Myeloid Leukemia (AML), Large-Cell Immunoblastic Lymphoma, Leukemia, and Salmonella Enterocolitis.

      Experienced in RASopathies

      Georges B. Nassrallah
      Experienced in RASopathies

      Georges B. Nassrallah
      Toronto, ON, CA 

      Georges Nassrallah practices in Toronto, Canada. Mr. Nassrallah is rated as an Experienced expert by MediFind in the treatment of RASopathies. His top areas of expertise are Ectropion, Petrositis, Orbital Cellulitis, Vitrectomy, and Cataract Removal.

      Experienced in RASopathies

      Roberto Londono-Mendoza
      Experienced in RASopathies

      Roberto Londono-Mendoza
      Toronto, ON, CA 

      Roberto Londono-Mendoza practices in Toronto, Canada. Mr. Londono-Mendoza is rated as an Experienced expert by MediFind in the treatment of RASopathies. His top areas of expertise are CHARGE Syndrome, Ehlers-Danlos Syndrome (EDS), Coloboma, and Nicolaides-Baraitser Syndrome.

      Experienced in RASopathies

      William L. Wong
      Experienced in RASopathies

      William L. Wong
      Kitchener, ON, CA 

      William Wong practices in Kitchener, Canada. Mr. Wong is rated as an Experienced expert by MediFind in the treatment of RASopathies. His top areas of expertise are Hepatitis C, Hepatitis, Hepatitis B, Liver Cancer, and Liver Transplant.

      While we make every effort to provide the best results possible, data is currently limited outside of the United States. Doctors listed may include both clinicians and researchers, and individuals relocate frequently. We recommend contacting doctors directly to confirm their location and areas of focus. Contact information is provided when available. Learn more about our expert tiers.
      Showing 1-20 of 44

      Last Updated: 01/09/2026

      What is the definition of RASopathies?

      RASopathies are a group of rare syndromes causes by mutations in the genes that make proteins for the Ras/MAPK cell signaling pathway. This pathway controls cell functions such as cell growth, cell maturation, and cell death. There are several types of RASopathy syndromes, including cardiofaciocutaneous syndrome, Costello syndrome, Legius syndrome, neurofibromatosis type 1, Noonan syndrome, and capillary malformation-arteriovenous malformation syndrome.

      When should I see a RASopathies doctor in Ontario, CA?

      There are various reasons why you may want to see a specialist, such as: 

      • Your primary care provider recommends it. 
      • Your condition requires expert knowledge and specialized care. 
      • Your symptoms persist or worsen despite treatment. 
      • You need specialized testing or procedures. 
      • You want a second opinion.  

      What should I consider when choosing a RASopathies doctor in Ontario, CA?

      It’s important to see a provider with expertise in your specific condition. Each provider profile in MediFind’s doctor database includes information on which conditions they treat, years of experience, research contributions, languages spoken, insurance plans accepted, and more.  

      How do I find the best RASopathies doctor in Ontario, CA?

      You can find a RASopathies doctor in any of the 10 largest U.S. cities by clicking below:

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      RASopathies doctor near San Jose, CA

      How does MediFind rank RASopathies doctors in Ontario, CA?

      MediFind’s rankings are based on a variety of data sources, such as the number of articles a doctor has published in medical journals, participation in clinical trials and industry conferences, as well as the number of patients that provider sees for a given condition. Note that MediFind’s provider database is not based on user reviews, and providers do not pay to be included in the database. 

      What types of insurance are accepted by RASopathies doctors in Ontario, CA?

      Most profiles in MediFind’s doctor database include a list of insurance plans accepted by that provider. However, it’s a good idea to contact the provider’s office to make sure they still accept your insurance, then doublecheck by contacting your insurance plan to confirm they’re in network. 

      How can I book an appointment online with a RASopathies doctor in Ontario, CA?

      MediFind offers direct scheduling for certain providers using the “Request Appointment” button on that provider’s profile. If the schedule option is not available for a provider, tap the red “Show Phone Number” button on their profile to get their contact information. If you prefer to find providers who offer online scheduling, select “Schedules online” under the “Availability” category of the filter feature on the left side of the RASopathies doctor search results page. 

      Why is it important to get a second opinion from a different RASopathies doctor?

      Second opinions are an opportunity to confirm a diagnosis and its root cause, learn about alternative treatment options, or simply gain peace of mind. Many people, especially those with serious diagnoses, get second opinions so they can understand all their options and make informed decisions, so don’t hesitate to get one if you have any doubts or need more information or clarification regarding your care. Note that some insurance plans require second opinions, while others don’t cover second opinions, so be sure to confirm with your insurance provider first.   

      How can I prepare for my appointment with a RASopathies doctor in Ontario, CA?

      Prepare for your appointment by gathering the following items: 

      • Copies of medical records (dating back at least one year) 
      • Your medical history, including illnesses, medical conditions, surgeries, and other doctors you see 
      • Family history of disease 
      • List of current prescription drugs, over-the-counter medicines, vitamins, and herbal remedies or supplements including names and doses 
      • Allergies to medications, food, latex, insects, etc.  
      • List of questions and concerns 
      • Your insurance card 

      You might also contact the provider’s office to see if they offer transportation or childcare services or if you’re allowed to bring a loved one for support or to take notes during your visit. 

      What questions should I ask my RASopathies doctor?

      Here are some sample questions: 

      • Can you explain in simple terms what this condition is and how it’s treated? 
      • What symptoms or side effects should I watch for? 
      • What tests will be involved, and when can I expect results? 
      • Are there other specialists I need to see? 
      • What’s the best way to reach you if I have follow-up questions? 

      How can I learn about the latest clinical trials and research advances my RASopathies doctor may know about?

      MediFind’s Clinical Trials tool asks you a series of questions to help you narrow down your search by health condition, age, gender, location, how far you’re willing to travel, and more. Each question you answer filters down the number of trials until you find the ones that are most relevant to you. 

      MediFind’s Latest Advances tool features summaries of recent articles published in medical journals. We use cutting-edge technology to scour medical publication databases for the latest research advancements on any given condition, then we simplify this information in a way that’s useful and easy to understand. 

      Can I filter my search to show male or female RASopathies doctors in Ontario, CA?

      Look for the filter feature on the left side of the RASopathies doctor search results page. Select “Female” or “Male” under the “Gender” category to search for female or male providers exclusively. If the “Any” option is selected, it will pull results for both male and female providers. 

      Can I filter my search to find a RASopathies doctor that offers video calls?

      Look for the filter feature on the left-side of the RASopathies doctor search results page. Select “Offers telehealth visits” under the Availability category to search for providers who offer virtual appointments (video calls). 

      Reviewed on: 11/11/24  

      By: MediFind Medical Staff 

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