Coffin-Siris syndrome

Coffin-Siris syndrome is a rare genetic condition first described in 1970 by Dr Coffin and Dr Siris, and is found in both males and females.

In this article

What are the symptoms of Coffin-Siris syndrome?

The most common clinical features are:

  • short fifth fingers and/or toes
  • absent or under-developed nails on the fifth fingers and/or toes
  • characteristic facial features (thick, bushy eyebrows, long eyelashes, a wide mouth with thick lips, a flat nasal bridge and a wide nasal tip)
  • mild to severe developmental delay (see entry Global Developmental Delay) or learning disability (see entry Learning Disability).

Excess body hair (called hypertrichosis or hirsuitism, depending on the pattern) and sparse scalp hair are also very common.  

Expressive speech delay is often particularly affected, although children may also have difficulties with their gross motor skills (e.g. sitting and walking), fine motor skills (e.g. hand use) and with their hearing and vision.  

Individuals with Coffin-Siris syndrome often have problems with feeding and growth. They may be more bendy (lax-jointed) or have lower muscle tone than other children. Other problems include spinal curvature, recurrent infections and unusual teeth. Less commonly, heart, gut, brain or kidney problems, a cleft palate, seizures, hernias and tear duct abnormalities may be found. Not all of these features would be expected to be found in one individual.

What are the causes of Coffin-Siris syndrome?

Some (but not all) individuals with Coffin-Siris syndrome have been found to have an alteration in one of a group of five genes (ARID1A, ARID1B, SMARCA4, SMARCB1 and SMARCE1). The cause in those without an identifiable gene alteration is still unknown. Some children with changes in one of these genes may have learning disability but no other specific features of Coffin-Siris syndrome.

How is Coffin-Siris syndrome diagnosed?

As it is such a rare condition and some of the features may be found in association with other conditions, diagnosis is usually made by a clinical geneticist, based on clinical findings. Genetic testing for Coffin-Siris syndrome is not currently available through the NHS, though many individuals will be offered other tests to rule out similar conditions before the diagnosis is made. In the future, it is likely that genetic testing for Coffin-Siris syndrome may be more widely available and that diagnostic and/or testing criteria may be developed.

How is Coffin-Siris syndrome treated?

Individuals with Coffin-Siris syndrome are likely to be under regular follow up with hospital and/or community paediatricians who can monitor growth and development and investigate any health concerns. Specialist paediatricians such as gastroenterologists, neurologists, orthopaedic surgeons, ophthalmologists, ear, nose and throat specialists and dentists and others may also need to be involved in an individual’s care. Individuals with Coffin-Siris syndrome are also likely to need vision and hearing tests, and may require the involvement of other health professionals such as feeding specialists, physiotherapists, speech therapists and occupational therapists. As a child gets older, their educational needs will also need to be addressed.

Inheritance patterns and prenatal diagnosis

Inheritance patterns
Alterations in the five genes currently known to be associated with Coffin-Siris syndrome most commonly arise for the first time in the affected individual and are not inherited. This means that in a child known to have an alteration in one of these genes, there is usually a low chance that their parents will have another affected child. However, there are rare exceptions, and it is still possible that the condition could have been inherited from one or both parents. It is therefore important that families with children with Coffin-Siris syndrome are offered referral to a clinical geneticist and genetic counselling.

Prenatal diagnosis
Prenatal diagnosis may be available if the gene alteration has been identified in the affected individual.

Is there support for people affected by Coffin Siris Syndrome and their families?

If your child is affected by a medical condition or disability, we can help. Call our freephone helpline on 0808 808 3555 to get information, support and advice. We also offer emotional support for parents via our Listening Ear service.

We have a range of parent guides on aspects of caring for a disabled child in our resource library. You may also find our Early Years Support useful, which contains links to parent carer workshops and help for families going through the diagnosis process.

We’ve listed some support groups below and you can also meet other parents online in our closed Facebook group.

Coffin Siris Syndrome Support Network

Tel: 01254 479758

The Network is a small group of parents, established in 2000. It offers support and a listening ear to families in the UK and has links with families around the world. They also offer an opportunity to network with others via their Facebook group.

Group details last updated January 2023.


Medical text written November 2008 by Dr Caroline Pottinger. Last reviewed September 2013 by Dr Caroline Pottinger, Consultant Clinical Geneticist, All Wales Medical Genetics Service, Clinical Genetics Department, Glan Clwyd Hospital, Wales, UK, and Professor Jill Clayton Smith, Consultant Clinical Geneticist, Academic Unit of Medical Genetics and Regional Genetic Service, Central Manchester and Manchester Children’s University Hospitals NHS Trust and Honorary Professor in Medical Genetics, School of Medicine, Division of Human Development, Faculty of Medical and Human Sciences, University of Manchester, UK.

Back to A-Z Conditions