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Gorlin Syndrome Group

Supporting patients, their families and carers
 
Registered Charity No: 1096361
Supporting patients, their families, friends and carers affected by Gorlin Syndrome
Home      Diagnosis

Diagnosis
Early diagnosis is vital for subsequent surveillance for complications such as basal cell carcinomas and jaw cysts, and for giving genetic information.



Diagnosis of Gorlin Syndrome
Patients can present to different specialists, depending on the first sign of the syndrome. It is very common for families to remain undiagnosed for several generations despite having been seen by doctors from a variety of disciplines.

Diagnosis in a child at 50% risk of having inherited the condition may not be easy because of the extreme variation in expression, both within and between families. Some children may have only rib anomalies whilst others have the "typical face" without other signs. Gene tracking and mutation analysis may be helpful for presymptomatic diagnosis.

For apparently isolated cases, detailed examination and X-ray investigation of the parents should be undertaken before concluding that a child's condition is the result of a new mutation. If an adult has no physical signs, no pertinent history and normal radiology, it is unlikely that he or she has Gorlin syndrome. Direct mutation analysis of the gene may be helpful.

Physical Examination

Particularly helpful are skeletal anomalies, typical faces, naevi and palmar and plantar pits. The most valuable measurement is the head circumference. Measurements should also include height, inner- and outer-canthal and interpupillary distances. The head circumference should be plotted on a chart which takes height into account. X-ray may aid diagnosis in those who have equivocal physical signs. X-rays should include:
 
  Skull - AP and lateral
  Panoramic views of the jaws (plain films may miss lesions) 
  Chest x-ray
  Cervical and thoracic spine - AP and lateral
  Hands (for pseudocysts)   




 
Confirmation of disease status by gene tracking
 
As locus heterogenity has not been reported, presymptomatic  and prenatal diagnosis is possible by gene tracking using DNA markers from 9q22.3-q31.  For an individual family this will depend on the availability of  DNA samples from appropriate  family members. There several highly informative DNA markers within and flanking the gene, resulting in a high accuracy of prediction.
 




Confirmation of diagnosis by mutation analysis

The definitive diagnostic test is to demonstrate a mutation in the patched gene, although this can be labour intensive as there are 24 exons. It is available through the NHS in the UK.
 

Genetic Testing
 
is available at 23 regional genetics centres throughout the  UK. A list of the centres can be accessed is available on this  website under the Genetics menu.
 

 


 
 
 
Written and produced by Professor P A Farndon, Clinical Geneticist at the National Genetics Education and Development Centre UK, Jim Costello (deceased) & Margaret Costello, unless otherwise stated.