Nodes Needing Neurofascin
November 26, 2014
The exome is the protein coding portion of the genetic code. Whole exome sequencing is an emerging diagnostic approach for efficiently identifying molecular defects in patients with rare Mendelian genetic disorders, including those with neurologic disorders (1). Typical genetic tests focus on locus-specific or gene panel testing often with limited yield or rely on assessment of the entire genome requiring expensive evaluation of noncoding regions that can often be difficult to interpret. In contrast, exome sequencing screens the 3% of coding genes, thus focusing on the functionally important part of the genome. DNA from blood samples is sequenced nucleotide by nucleotide to build a patient-specific consensus sequence. This consensus is compared to known standard sequences to determine putative genetic abnormalities.
- Yang Y, Muzny DM, Reid JG, et al. Clinical whole-exome sequencing for the diagnosis of Mendelian disorders. NEJM 2013;369:1502-1511.
Submitted by Roy Strowd, MD, Clinical Neuro-Oncology Fellow, Johns Hopkins Hospital, Baltimore, MD.
Dr. Strowd is a member of the Resident and Fellow Section of Neurology.