Chromosome 15q11.2-13.1 duplication syndrome (Dup15q syndrome) is a chromosomal condition. It occurs when there is one or more extra (duplicate) copies of a section of Chromosome 15. This section on Chromosome 15 is known as 15q11.2-13.1 or the Prader-Willi/Angelman critical region (PWACR).^1,2 In some individuals, duplication of the region could be due to having a whole extra chromosome 15 (isodicentric duplication), whilst for others, the 15q11.2-13.1 region is repeated (more than one copy) on one of their chromosome 15 (interstitial duplication).^1-3 The size of the duplicated region (and the genes that are affected) can also differ between individuals.¹ The duplication may be inherited, usually more often from the mother than the father, or may occur spontaneously (de novo).³ Maternally inherited (from the mother) duplications tend to result in severe symptoms than those paternally inherited (from the father).^1,3 Common features of Dup15q syndrome include low muscle tone (hypotonia) in newborns, delays in motor skills, speech and language, intellectual disability, autism spectrum disorder (ASD) and seizures.^1-3

Synonyms: 15q11q13 microduplication syndrome; Dup(15)(q11q13); Trisomy 15q11q13.¹

Universal rare disease classifications provide a common language for recording, reporting and monitoring diseases. Please visit the Rare Disease Classifications page for more information about these internationally recognised classifications.

ORPHA:238446 15q11q13 microduplication syndrome

ICD-11: LD41.E Duplications of chromosome 15

Common features of Dup15q syndrome include low muscle tone (hypotonia) in newborns, delays in motor skills, speech and language, intellectual disability, autism spectrum disorder (ASD) and seizures.^1-3

Individuals with Dup15q syndrome may have facial features such as downward slanting of the space between the eyelids (downslanting palpebral fissures), wide upper nose area (broad nasal bridge), single eyelid fold (epicanthal folds) and full lips.^1-4 These features are known as dysmorphic and may not always be very noticeable.²

The symptoms and severity of Dup15q syndrome often vary between individuals. Please speak to your medical team to learn more about the signs and symptoms of Dup15q syndrome.

Rare diseases are often serious and progressive, exhibiting a high degree of symptom complexity, leading to significant disability. Majority of the estimated two million Australians living with a rare disease meet the Australian Government’s definition for disability (in accordance to the Australian Public Service Commission and Australian Bureau of Statistics), and many experience severe and permanent disability impacts. If you or someone you care for is experiencing disability-related impacts from a rare condition, please speak with a health or disability professional for advice. Information about relevant disability support can be found at the RARE Portal’s Disability Support Information page.

Dup15q syndrome is caused by extra copies (duplicate) of a portion of Chromosome 15 at the region 15q11.2-13.1.^1-3 It is a type of chromosomal abnormality. The duplication can be in the form of an extra chromosome 15 (isodicentric duplication) or can be a duplication located on one of the existing chromosome 15 (interstitial duplication).^1-3 The duplication may be inherited, more often from the mother than the father, or may occur randomly.³

If you would like to learn more about the inheritance and impact of this condition, please ask your doctor for a referral to a genetic counsellor. Genetic counsellors are qualified allied health professionals who can provide information and support regarding genetic conditions and testing. More information about genetic counselling can be found at:

• Information on Genetic Services
• The National and State Services pages underneath the ‘Genetic Counselling’ sections listed

A Dup15q syndrome diagnosis may be considered for children with low muscle tone at early age (early hypotonia), dysmorphic features, developmental delay, intellectual disability, autism spectrum disorder (ASD), seizures.^1,2

Diagnosis of Dup15q syndrome is usually confirmed using chromosome studies such as cytogenetic karyotyping to look for large duplications or chromosome microarray analysis to identify smaller duplications (microduplications).²

Further information about the diagnostic tests can be found at:

• Pathology Tests Explained: Chromosome studies
• Pathology Tests Explained: Genome-wide chromosome microarray testing

A differential diagnosis can rule out other conditions that have similar symptoms, such as other chromosomal abnormalities and causes of developmental delay, intellectual disability and ASD, and seizures.^1,4

Please speak to your medical team to learn more about the available diagnostic pathways for Dup15q syndrome.

There is currently no curative treatment for Dup15q syndrome. Treatment is targeted at managing symptoms (symptomatic management) and involves a multidisciplinary care team. This may include physical therapy, occupational therapy , speech therapy, behavioural interventions, use of assistive devices such as augmentative and alternative communication tools, nutritional support and seizure management.^1,2,4

Please speak to your medical team to learn more about the possible treatment or management options for your condition. Treatment will depend on an individual’s specific condition and symptoms. It is also important to stay connected to your medical team so that you can be made aware of any upcoming clinical trial opportunities.

Clinical care for rare diseases often involves a multidisciplinary team of medical, care and support professionals. Please note that the information provided here is as a guide and that RVA does not necessarily monitor or endorse specific clinics or health experts.

Healthcare professionals involved in the treatment of Dup15q syndrome may include general practitioners (GP), paediatricians, geneticists, neurologists, physiotherapists, speech therapists, occupational therapists and ophthalmologists. The need for different healthcare professionals may change over a person’s lifetime and extend beyond those listed here.^2,4

We are not aware of any clinical care guidelines for Dup15q syndrome in Australia. If you know of any relevant care guidelines, please let us know via the Contribute page.

Individuals living with rare diseases may have complex medical issues and disabilities, which are not always visible. It is often useful to refer to their medical history as well as personal information such as a medical card, doctor’s letter, or if available, a rare disease passport, for relevant information.

There are specific considerations around participating in rare disease research, including clinical trials. It is important to be mindful of issues such as data privacy, research ethics, consent and differences in research regulations between Australia and other countries.

If you are interested in finding clinical trials for your condition, please visit the following websites; however, there may not be any clinical trials available:

• Australian Clinical Trials
• ClinicalTrials.gov

It is best to discuss your interest in any clinical trials with your medical team to determine suitability and eligibility.

Please note that RVA does not necessarily monitor or endorse each group/organisation’s operational governance and activities.

International Organisation:

Dup15q Alliance (United States of America)
Website: https://dup15q.org/

Please note that RVA does not monitor or endorse each group/organisation’s operational governance and activities. When engaging with a group, please consider the information on the RARE Portal’s Finding Helpful Peer and Community Supports page.

Dup15q syndrome vary between individuals, and each person’s experience is unique.

If you would like to share your personal story with RVA, please visit the Rare Voices Australia: Share Your Story page. RVA will consider your story for publishing on our website and inclusion on the RARE Portal.

For information on available government and social services that provide support for individuals with a rare disease, please visit the National and State Services pages.

People living with a rare disease, including families and carers, often face unique challenges such as diagnostic delays, misdiagnoses, limited treatment options, and limited access to rare disease specialists and support. These challenges may impact people’s emotional wellbeing and quality of life. Many people find it helpful to seek mental health and wellbeing support to cope with ongoing stress and uncertainty. Connecting with people who have shared experiences through a support group may also be helpful. Information about relevant mental health and wellbeing support can be found at:

• Mental Health and Wellbeing Support for Australians Living with a Rare Disease
• The National and State Services pages underneath the ‘Mental Health’ sections listed

Further information on Dup15q syndrome can be found at:

• Genetic and Rare Diseases (GARD) Information Center: Chromosome 15q duplication
• National Organization for Rare Disorders (NORD): Dup15q syndrome
• Unique – Understanding Rare Chromosome and Gene Disorders: 15q duplications

• Online Mendelian Inheritance in Man (OMIM): #608636 – CHROMOSOME 15q11-q13 DUPLICATION SYNDROME
• Orphanet: 15q11q13 microduplication syndrome
• GeneReviews®: Maternal 15q Duplication Syndrome

This page has been co-developed by Rare Voices Australia (RVA) in consultation with a lived experience expert.

If you are aware of any additional information that may benefit stakeholders with an interest in this page, or if you notice any broken links or inaccurate information, please let us know via the Contribute page.