Rubinstein Taybi syndrome: Broad Thumb-Great Toe syndrome

Children with Rubinstein-Taybi syndrome (RTS) usually have normal birthweights, but subsequent growth is poor, with most children being of short stature with a small head size. Developmental delay is usual, but varies from mild to severe. The most striking physical feature is broad, sometimes angulated thumbs and first toes. The facial features vary with age and include a prominent beaked nose and downslanting eyes. Undescended testes occur in males. Other variable features include congenital heart disease and kidney abnormalities, eye and hearing problems, feeding difficulties in infancy and constipation. Seizures may occur. Most people with Rubinstein-Taybi syndrome have friendly and loving personalities.

Inheritance patterns
Rubinstein-Taybi syndrome, although a genetic disorder, usually affects only a single person in the family. Changes (mutations or deletions) in a gene called CREBBP located on chromosome 16 are found in a significant number of people with RTS. These changes are sometimes seen on chromosome analysis but often will require special laboratory techniques to be found. These are usually new genetic changes in just the affected person. If the parents of a child with RTS have normal chromosomes, the chance of a second affected child is small, around one per cent. If, however, an individual with RTS has children of their own, the chance for a similarly affected child may be as high as fifty per cent.

Prenatal diagnosis
If the genetic change is known in an affected child, pre-natal diagnosis may be possible to reassure parents.

Medical text written July 1998 by Dr Bronwyn Kerr. Last updated October 2003 by Dr Bronwyn Kerr, Consultant Clinical Geneticist, Royal Manchester Children's Hospital, Manchester, UK.

The information below has been drawn up by Dr Orlee Udwin of the Society for the Study of Behavioural Phenotypes.

Psychological and behavioural characteristics
Children with Rubinstein-Taybi syndrome show similarities in their intellectual profiles and behaviour. Most have moderate to severe learning difficulties, though some have mild learning difficulties. Overall, visuo-spatial and motor abilities tend to be better than verbal abilities. Expressive language is particularly limited, and some affected children do not develop speech at all, although they can benefit from signing and a 'total communication' approach to language teaching. In general affected individuals are able to use their limited speech communicatively, and show overall good language competency. Poor concentration and distractibility are further common features.

The children are frequently described as happy, loving and easy to get on with. They are very sociable, even over-friendly, and love adult attention. They are reported to be particularly responsive to music and are very interested in manipulating objects such as electronic appliances and dials. Most become self-sufficient in eating, dressing and toileting. Severe sleep disturbance is reported in some cases and may be the result of frequent waking in the night due to breathing difficulties.

Over half of the children are said to engage in self-stimulatory behaviours such as rocking, hand flapping and spinning. Many also show resistance to environmental change, intolerance to loud noises and self-injurious behaviours. Older individuals may show sudden changes in mood and temper outbursts.

Further Online Resources
Medical texts in The Contact a Family Directory are designed to give a short, clear description of specific conditions and rare disorders. More extensive information on this condition can be found on a range of reliable, validated web sites and links to them are included in the CD-ROM version of this Directory. Further information on these resources can be found in our Medical Information on the Internet article.

RUBINSTEIN TAYBI SYNDROME SUPPORT GROUP

Rubinstein Taybi Syndrome Support Group
162 Buckfield Road
Leominster HR6 8UF
Tel: 01568 616149
e-mail: magsruck@blueyonder.co.uk
Web: http://www.rtsuk.org

The Group is a National Registered Charity No. 1037043, established in 1986. It offers support to families and linking with others where possible. It also has an area family network. It publishes a newsletter twice a year and has information available, details on request. The Group has over 200 UK and overseas families on its mailing list.

Group details last confirmed November 2007.