Related Experiment Video
Updated: Mar 19, 2026
A Strategy to Identify de Novo Mutations in Common Disorders such as Autism and Schizophrenia
Published on: June 15, 2011
Exome Sequencing and the Management of Neurometabolic Disorders
Maja Tarailo-Graovac1, Casper Shyr1, Colin J Ross1
1From the Centre for Molecular Medicine and Therapeutics (M.T.-G., C. Shyr, X.C.Y., L.-H.Z., J.J.Y.L., B.I.D., I.G., W.W.W., C.D.K.), the Departments of Medical Genetics (M.T.-G., C. Shyr, C.J.R., X.C.Y., J.J.Y.L., L.A., J.M.F., S.L., M.M., M.I.V.A., A.M.L., W.W.W.), Pediatrics (C.J.R., G.A.H., R.S., L.-H.Z., A.P.B., B.I.D., M.B.C., M.D., T.D., J.D., A. Michoulas, D.M., J.R., K.R.S., K.S., S.E.T., John Wu, S.S.-I., C.D.K.), and Pathology and Laboratory Medicine (B.R., P.E., H.V., G.S.), the Child and Family Research Institute (M.T.-G., C. Shyr, C.J.R., G.A.H., X.C.Y., A.P.B., J.J.Y.L., B.I.D., L.A., M.B.C., M.D., J.D., J.M.F., I.G., S.L., M.M., D.M., J.R., K.R.S., K.S., S.E.T., M.I.V.A., John Wu, P.E., A.M.L., H.V., S.S.-I., G.S., W.W.W., C.D.K.), and the Division of Endocrinology, Adult Metabolic Diseases Clinic (A. Mattman, S. Sirrs), University of British Columbia, and the Divisions of Biochemical Diseases (G.A.H., R.S., B.S., S.S.-I., C.D.K.), Pediatric Neurology (M.B.C., M.D., A. Michoulas, K.S.), Pediatric Nephrology (J.D.), Pediatric Endocrinology (D.M.), and Immunology (S.E.T.) and the Division of Hematology, Oncology and Transplantation, Michael Cuccione Childhood Cancer Research Program (J.R., K.R.S., John Wu), BC Children's Hospital, Vancouver, the Department of Pathology and Laboratory Medicine, Hospital for Sick Children, University of Toronto, Toronto (J.C.), the Department of Biological and Computing Sciences, University of Alberta (R.M., D.W.), and the National Institute for Nanotechnology (D.W.), Edmonton, AB, and the Department of Biomedical Physiology and Kinesiology, Simon Fraser University, Burnaby, BC (M. Abdelsayed, P.R.) - all in Canada; the Division of Genetics, Department of Pediatrics, King Saud Bin Abdulaziz University for Health Sciences, King Abdulaziz Medical City, Riyadh, Saudi Arabia (M. Alfadhel); the Division of Metabolism and Children's Research Center, University Children's Hospital Zurich, Zurich (M.R.B., P.B.), and the Departmen
Background:
Whole-exome sequencing has transformed gene discovery and diagnosis in rare diseases. Translation into disease-modifying treatments is challenging, particularly for intellectual developmental disorder. However, the exception is inborn errors of metabolism, since many of these disorders are responsive to therapy that targets pathophysiological features at the molecular or cellular level.
Methods:
To uncover the genetic basis of potentially treatable inborn errors of metabolism, we combined deep clinical phenotyping (the comprehensive characterization of the discrete components of a patient's clinical and biochemical phenotype) with whole-exome sequencing analysis through a semiautomated bioinformatics pipeline in consecutively enrolled patients with intellectual developmental disorder and unexplained metabolic phenotypes.
Results:
We performed whole-exome sequencing on samples obtained from 47 probands. Of these patients, 6 were excluded, including 1 who withdrew from the study. The remaining 41 probands had been born to predominantly nonconsanguineous parents of European descent. In 37 probands, we identified variants in 2 genes newly implicated in disease, 9 candidate genes, 22 known genes with newly identified phenotypes, and 9 genes with expected phenotypes; in most of the genes, the variants were classified as either pathogenic or probably pathogenic. Complex phenotypes of patients in five families were explained by coexisting monogenic conditions. We obtained a diagnosis in 28 of 41 probands (68%) who were evaluated. A test of a targeted intervention was performed in 18 patients (44%).
Conclusions:
Deep phenotyping and whole-exome sequencing in 41 probands with intellectual developmental disorder and unexplained metabolic abnormalities led to a diagnosis in 68%, the identification of 11 candidate genes newly implicated in neurometabolic disease, and a change in treatment beyond genetic counseling in 44%. (Funded by BC Children's Hospital Foundation and others.).
More Related Videos
08:22A Novel Strategy Combining Array-CGH, Whole-exome Sequencing and In Utero Electroporation in Rodents to Identify Causative Genes for Brain Malformations
Published on: December 1, 2017
09:34Targeted Next-generation Sequencing and Bioinformatics Pipeline to Evaluate Genetic Determinants of Constitutional Disease
Published on: April 4, 2018
Related Concept Videos
01:20Inborn Errors of Metabolism
02:59Animal Mitochondrial Genetics
03:00Next-generation Sequencing
Next-Generation Sequencing Methods
Although all next-generation methods use different technologies, they all share a set of standard features....
02:02Genomics