Seminar Series : Seminars Series II

Whole Exome Sequencing: The New Diagnostic Method for Genetic Disorders

Whole Exome Sequencing: The New Diagnostic Method for Genetic Disorders

Currently, over 4,000 monogenic syndromes have been described, but for nearly two-thirds of these, the molecular basis has not been identified due to the limitations of appropriate families or technology (www.omim.org). Recently, whole exome sequencing (sequencing just the genes that code for the actual proteins) has been very successful in identifying the gene defect in these patients. Increasingly, these newly identified gene defects have led to successful therapeutic intervention for the patient or family members. More than half of these syndromes are characterized by one or more birth defects. In addition, by identifying specific mutations in specific birth defects, we can return to the medical genetics clinics with the information that can form the basis for genetic testing for these previously un-examined genetic disorders. This will lead to better reproductive counseling and prenatal or pre-implantation diagnosis, which in turn leads to preventing the disease from affecting the child and family. By identifying the genetic mutations in these disorders, this information can be incorporated into the databases for clinical sequencing in the future. It provides the opportunity to greatly reduce the occurrence of these syndromes. This is analogous to the 90% drop in the incidence of Tay-Sachs disease over the past decade due to carrier testing in the Ashkenazi Jewish population.