15q11.2 microdeletion syndrome is a chromosomal condition in which a small part of chromosome 15 is missing (deleted).¹ This small deletion, also known as a microdeletion, occurs at a location on chromosome 15 called 15q11.2, between two breakpoint sites called BP1 and BP2.² It causes the absence of four known genes — NIPA1, NIPA2, TUBGCP5 and CYFIP1.

Common features of 15q11.2 microdeletion syndrome include delays in development and speech, learning difficulties, behavioural issues as well as abnormalities of the ear (dysmorphic ears) and roof of mouth (palate).^2-5 Other features include abnormal reflexes, seizures, autism spectrum disorder, attention deficit disorders, and psychiatric issues such as schizophrenia. These features can vary widely between individuals, and not all individuals with a 15q11.2 microdeletion may display symptoms (incomplete penetrance).^2-3

15q11.2 BP1-BP2 Microdeletion Syndrome; Chromosome 15q11.2 Deletion; Chromosome 15q11.2 Microdeletion; Del(15)(q11.2); Monosomy 15q11.2²

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:261183 15q11.2 microdeletion syndrome

ICD-11:LD44.F Deletions of chromosome 15

The features of 15q11.2 microdeletion syndrome varies widely between individuals. Not all individuals with a 15q11.2 microdeletion display symptoms (incomplete penetrance).^2-3

Common features of 15q11.2 microdeletion syndrome include:^2-5

• developmental and speech delays
• abnormalities of the ears (dysmorphic ears) and roof of the mouth (palate)
• learning difficulties
• behavioural issues
• differences on neuroimaging (imaging of the brain)

Other features associated with 15q11.2 microdeletion syndrome include abnormal reflexes and coordination, seizures, autism spectrum disorder, attention deficient disorders, and psychiatric issues such as schizophrenia.^2-5

Please speak to your medical team to learn more about the features of 15q11.2 microdeletion 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.

This microdeletion may occur randomly (de novo mutation) in an affected individual before birth, or it may be inherited from a parent.^1-3 As some individuals with a 15q11.2 microdeletion do not display any symptoms, it is possible that a parent of an affected child may have an undetected microdeletion.

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

There are no formal clinical diagnostic criteria for 15q11.2 microdeletion syndrome.

Diagnosis of 15q11.2 microdeletion syndrome may be considered based on the characteristic features of the syndrome and confirmed by genetic testing to identify the deletion of genetic material on chromosome 15 at location q11.2.³

Please speak to your medical team to learn more about the available diagnostic pathways for 15q11.2 microdeletion syndrome.

There is currently no curative treatment for 15q11.2 microdeletion syndrome.³ Treatment is targeted at managing symptoms (symptomatic management) and involves a multidisciplinary care team. This may include occupational therapy, speech therapy, behavioural therapy, educational therapy, cleft palate surgery, treatment of seizures and psychiatric issues, and others.³

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 15q11.2 microdeletion syndrome may include general practitioners (GP), paediatricians, geneticists, ear, nose and throat (ENT) specialists, plastic surgeons, orthodontists, psychiatrists, neurologists, speech therapists, behavioural therapists and occupational therapists.^1,3 The need for different healthcare professionals may change over a person’s lifetime and extend beyond those listed here.

We are not aware of any clinical care guidelines for 15q11.2 microdeletion 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.

We are not aware of any rare disease organisations for 15q11.2 microdeletion syndrome in Australia or internationally. If you know of any rare disease organisation/s supporting people living with 15q11.2 microdeletion syndrome, please let us know via the Contribute page. If you are interested in starting an Australian organisation, please see Engaged, Ethical and Effective: A Guide for Rare Disease Organisation Leaders in Australia.

Genetics Alliance Australia (GAA) and Syndromes Without A Name (SWAN) Australia may be able to provide some support for families and individuals affected by an undiagnosed or rare genetic condition for which there is no disease specific organisation in Australia.

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.

15q11.2 microdeletion 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 15q11.2 microdeletion syndrome can be found at:

• Genetic and Rare Diseases (GARD) Information Center : Chromosome 15q11.2 deletion syndrome
• Unique: 15q11.2 microdeletions

• Online Mendelian Inheritance in Man (OMIM): #615656 Chromosome 15q11.2 Deletion Syndrome
• Orphanet: 15q11.2 Microdeletion Syndrome
• Human Phenotype Ontology (HPO): 15q11.2 Microdeletion Syndrome

This page has been developed by Rare Voices Australia (RVA)’s RARE Portal team.

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.