Medical Research Update 1999
We contacted members of our Editorial Advisory Board as well as other professionals who have contributed their knowledge to articles in Exceptional Parent, and asked them to share their perspectives on the most important current research in their respective fields or in general and its relevance to children and young adults who have special needs. These professionals, representing a range of disciplines, have responded with a thought-provoking body of information indicating some exciting possibilities for the future. We present their commits here.--The Editors
It is estimated that by the end of the year 2000, the entire human genome will have been "cloned." This means that scientists will have identified the 80,000 or so genes that serve as the blueprint for the production and function of a human being. This is but the first step of what we are hopeful will lead to the determination of which specific genes, when defective, cause various developmental disabilities. Once we can assess the linkage between these genetic defects and a developmental disorder, it may allow us to develop more specific and earlier approaches to the treatment of children with special needs. It is estimated that over half of all developmental disabilities in childhood are genetically determined or influenced. Thus these advances are likely to have a significant impact on the care of our exceptional children.
One such innovative approach is gene therapy. The idea here is to correct a disorder by giving copies of a new gene that will serve in place of the defective gene. This idea is currently being tested in certain inborn errors of metabolism of childhood. In these disorders, the gene "mutation," or error results in the deficient production of an enzyme that normally breaks down a toxic material produced by the body. A common example of an inborn error is PKU or phenylketonuria (a metabolic disorder caused by an enzyme deficiency. It involves accumulation of certain amino acids in body fluids, resulting in mental retardation). In PKU, specific dietary restriction has been found to have enormous benefit by preventing the buildup of toxins, but in many inborn errors, there remains no effective treatment. Gene therapy studies are now going on using viruses to act as "taxis" to move copies of the new gene into the body. These studies are being done first in animal models of human disease, to determine if gene therapy is feasible and safe. It is likely that gene therapy trials in children will become common over the next five years, with the goal that some of these will be successful, adding a new approach to our armamentarium for treatment of children with disabilities.
Mark L. Batshaw, MI). Chairman and Academic Children's National Medical Center Fight For Children Chair The George Washington University Washington D.C.
What is the most important research going on currently in the field of developmental disabilities? That is a tough call, but I would like to offer the following list of a dozen topics that are of a crucial nature, in terms of the goals they seek to reach:
(1) Use of improved genetic technology from the Human Genome Project for clarification of the "nosology" or classification of certain disorders, analysis of complex inheritance patterns, and the presence of relevant host factors.
(2) A greater understanding of the foundations of autism, acknowledging its apparent "heterogeneity," partial genetic elements, and increased incidence.
(3) Insight on the special relationship of the thyroid gland to the genesis of Trisomy 21 (Down syndrome) and to the optimal long-term course of involved persons.
(4) Identification of the basic cause of Rett syndrome (a degenerative disease behaviorally somewhat similar to autism) where a biologic origin seems probable but has been elusive.
(1) Further development of the capacity for enzyme replacement therapy, noting the current promise in Hurler syndrome, one of the mucopolysaccharidoses (MPS)disorders. …