Children's Hospital Colorado
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About the Chromosome 15 and Related Disorders Clinic

We understand the complex health needs of children and adults with Angelman syndrome, dup15q syndrome, Pitt-Hopkins syndrome and related genetic disorders. The Chromosome 15 and Related Disorders Clinic brings together doctors and providers from many specialties for complete care based on the latest research.

These rare genetic disorders cause a variety of symptoms that affect a person’s physical, cognitive (thinking) and behavioral abilities. We provide a wide range of services that help with every aspect of health and development.

Our specialists are committed to helping children and adults with chromosome 15 disorders achieve their full potential for a happy, active life. Our team includes providers in:

Why choose us for chromosome 15 and related disorders care?

Our clinic is part of the Neuroscience Institute and the Genetics and Inherited Metabolic Diseases Program at Children’s Hospital Colorado, recognized worldwide for expert neurological care for babies, children and young adults. We offer highly specialized care at the only clinic in the Rocky Mountain region for people with Angelman syndrome, dup15q syndrome and related disorders.

Families come to us because we offer:

A medical home for families coping with chromosome 15-related disorders

Children and adults who have Angelman, dup15q and related syndromes get compassionate care with a focus on how these disorders affect the entire family. We partner with you and your child, listening closely to your concerns to ensure that we meet your family’s needs. Our specialists plan your care to support your child’s best health at every life stage. Our experts ensure that you and your child’s doctor always have someone to turn to for any question or concern with access to:

  • A nurse coordinator during business hours at 720-777-1942
  • Emergency consultations, available 24/7 for providers, at 720-777-0015 (ask for the Angelman provider on call)

Complete care for chromosome 15 disorders

Our clinic was founded by Jessica Duis, MD, MS, a pediatric geneticist and special care pediatrician, and is co-directed by Diana Walleigh, MD, an epileptologist (doctor who specializes in epilepsy care). We lead a multispecialty team that provides ongoing care tailored to each person, including adults. Families and patients see eight specialists together in one visit.

The teams then work with you to develop a comprehensive care plan that addresses all of your child’s needs. And we continue to see your child for as long as they need us — even into adulthood.

World-renowned experts in chromosome 15 care

With vast expertise in chromosome 15 and related disorders, our team has received recognition from patient-centered organizations across the world:

  • The Angelman Syndrome Foundation (ASF) and the Dup15q Alliance have named our program as a center of excellence for each syndrome.
  • We’re recognized as one of the only multidisciplinary centers of excellence in the world for Pitt-Hopkins syndrome by the Pitt-Hopkins Research Foundation.
  • Our doctor-researchers have received funding from ASF, Dup15q Alliance and the Foundation for Angelman Syndrome Therapeutics (FAST) for clinical research.
  • We conduct clinical trials for people with Angelman syndrome and related disorders.
  • Funded by FAST, we established the first-of-its-kind, rare disease care hotline to ensure access to care for anyone who has Angelman syndrome.
  • Our Angelman Syndrome Center of Excellence has received a discovery grant from ASF to expand our services to include support for:
    • Educational services, including individualized education plans
    • Speech and language services, including augmentative and alternative communication (AAC) devices
    • Nutritional services, with a focus on low-glycemic-index therapy and ketogenic diets

Your child receives care from a team at the forefront of research and care for people who have chromosome 15 and related disorders. This means that we sometimes offer new and advanced treatments that aren’t available elsewhere.

An ongoing resource for families

Meeting with us is just the beginning of our relationship with your family. Our team provides care and support not just when you’re in our office, but anytime you need our help. You can reach us directly whenever you have questions.

24/7 emergency consultation for providers

Our specialists offer direct, provider-to-provider advice for doctors anywhere in the world caring for patients with Angelman syndrome. Providers can call 720-777-0015 or 1-800-525-4871 and ask for the Angelman provider on call 24/7 to receive expert guidance and support from one of our specialists. The hotline is the first of its kind for a rare genetic disorder.

Providers may also email us at

Opportunities to participate in the latest chromosome 15 research

We have several ongoing research studies on motor development, including gait (walking patterns). Our team also conducts clinical trials studying personalized therapies that target the gene associated with Angelman syndrome. If eligible for a study or trial, your child will have access to the latest therapies for chromosome 15 disorders. You may contact us to learn more at

Learn more about neuroscience research at Children’s Colorado

Who we treat at the Chromosome 15 and Related Disorders Clinic

Our team provides care in a medical home for people of all ages, from before birth through adulthood. We specialize in evaluation, diagnosis and treatment of conditions related to problems with chromosome 15, which include:

  • Angelman syndrome
  • Dup15q syndrome, also called chromosome 15 duplication
  • CHD2-related neurodevelopmental disorders
  • Pitt-Hopkins syndrome
  • Angelman-like syndromes, such as SYNGAP1-related intellectual disability and MEF2C haploinsufficiency syndrome

Contact the Chromosome 15 and Related Disorders Clinic

To learn more about our services or make an appointment, you or your child’s healthcare provider can contact us by:

Your health insurance plan may require a referral, which you or the provider can fax to 720-777-7974. Once we schedule your child’s appointment, we send you a survey and medical history to complete before your visit.

Get to know our pediatric experts.

Ann Reynolds, MD

Ann Reynolds, MD

Developmental/Behavioral Pediatrics

Susan Apkon, MD

Susan Apkon, MD

Pediatric Physical Medicine & Rehabilitation, Pediatrics, Physical Medicine & Rehabilitation

Diana Walleigh, MD

Diana Walleigh, MD

Neurology - Pediatric, Neurology, Pediatrics

Wendy Pierce, MD

Wendy Pierce, MD

Physical Medicine & Rehabilitation - Pediatric, Physical Medicine & Rehabilitation