Genetic testing in neurology

‘Neurogenetics’ spans almost every category of neurological disease (World Health Organization International Disease Classification: https://www.who.int/standards/classifications/classification-of-diseases), and genomic testing is increasingly important in the diagnosis and personalized management of these conditions. An understanding of the genetic basis of disease, genomic technologies and interpretation of increasingly complicated genomic data is essential for all clinicians. The likely disease aetiology and the utility of genomic testing must be considered as conditions might be caused by environmental adverse exposures (e.g. traumatic brain injury, infectious illness) or multifactorial risk factors (a combination of environmental and monogenic/polygenic influences). In this chapter, we focus on the basic concepts of neurogenetic disease, inheritance patterns and the laboratory techniques used in diagnosis. We also address important aspects in clinical practice, such as the resources used to guide clinicians to choose the ‘right’ test for their patients and families, the different types of genetic test and the clinical indications for each, the framework used to interpret genomic variants, ‘pre-test counselling’ and other ethical considerations.