Running a neurogenetic clinic
- Correspondence to: Dr MG Hanna, Neurogenetics Unit and DNA Laboratory, Department of Molecular Pathogenesis, Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK; mhanna{at}ion.ucl.ac.uk
As a group neurogenetic conditions are not rare. We estimate that approximately 10% of patients with neurological conditions have a single mutated gene as the basis for their disease. Furthermore, when polygenic inheritance is considered (that is, the interplay between multiple genes and environment) a much larger proportion of neurological diseases are included.
WHY HAVE NEUROGENETIC CLINICS?
The explosion of molecular genetic information over the last 10 years has resulted in a large number of genes being discovered for single gene disorders. Since the majority of the thousands of genes expressed in humans are in the nervous system (central and peripheral nervous systems), it is perhaps unsurprising that mutations in many of the discovered genes cause neurological disease. At present neurogenetic clinics are concerned mainly with addressing important issues in patients with these single gene disorders. However, once more is understood about the polygenic disorders, they are likely to be seen increasingly in neurogenetic clinics.
The immediate benefit of these discoveries to patients is in DNA based diagnosis. This accuracy will facilitate reliable genetic counselling and presymptomatic testing if required. For some neurogenetic conditions screening for the development of complications is made much more efficient by accurate DNA based diagnosis. This will allow screening only of definite gene mutation carriers, as opposed to all individuals potentially at risk in a family.
Unfortunately, there is often a long delay between gene discovery and the availability of DNA based tests for patients with a given neurogenetic condition. The existence of neurogenetic clinics in each region in the UK, and the associated infrastructure links with regional clinical genetics, should allow a more rapid translation of gene discovery into clinical neurogenetic practice. Such translation into clinical practice is often most rapid when the clinical and research teams already collaborate and/or are in the same physical location.
Although treatments …
