Autism is a neurodevelopmental disorder characterized by difficulties in social communication and repetitive behaviors. Autism now affects 1 in 88 children and 1 in 54 boys. Clinicians diagnose autism through behavioral evaluations. Research suggests that early intensive behavioral interventions are helpful for preschool children. More research is needed to understand whether other treatments may be helpful.
There is no one cause of autism. Genetic factors are clearly important in many cases. Environmental risk factors, primarily during pregnancy, also have an impact. Some emerging hypotheses about autism risk factors may provide clues to possible treatment.
One of the potential avenues to new ASD treatments is the connection to uncommon genetic syndromes that often include ASD symptoms. Fragile X Syndrome (FXS) is the most common known inherited strong risk factor for ASD. Researchers have identified medications that improve animal models of FXS and may help people with FXS as well. The same genetic pathways may be involved in a subgroup of children with ASD who do not have FXS. Medication treatment studies are underway to test if medications for FXS will help in ASD.
Studies in animal models, in the general human population, and in ASD show that single doses of oxytocin are capable of changing social behavior, including increasing interest in playing social games and improving ability to recognize emotions in others. In children with ASD, intranasal oxytocin changes the pattern of brain response to viewing human faces. Treatment studies are beginning to study whether oxytocin treatment helps with autism symptoms.
Molecular genetic and neuroscience research continues to identify possible avenues to treat ASD symptoms. We are committed to testing novel ideas as they emerge.
Down syndrome is the most common genetic condition in the United States with 1 in every 691 babies born with Down syndrome. Each year approximately 6,000 babies with Down syndrome are born in the United States. Down syndrome is caused by a full or partial extra copy of chromosome 21. All people with Down syndrome experience cognitive delays. In recent history, advances in medicine and science have enabled researchers to investigate the characteristics of people with Down syndrome. In 1959, the French physician Jérôme Lejeune identified Down syndrome as a chromosomal condition. Instead of the usual 46 chromosomes present in each cell, Lejeune observed 47 in the cells of individuals with Down syndrome. It was later determined that an extra partial or whole copy of chromosome 21 results in the characteristics associated with Down syndrome. In the year 2000, an international team of scientists successfully identified and catalogued each of the approximately 329 genes on chromosome 21. This accomplishment opened the door to great advances in Down syndrome research
Fragile X Syndrome
Fragile X Syndrome (FXS) is the most common inherited cause of intellectual disability. Many people with Fragile X also have co-occurring autism spectrum disorder. FXS is caused by a loss of FMR1 gene expression that can contribute to symptoms such as social impairment, anxiety, behavioral problems and hyperactivity. Boys are typically more affected than girls and a diagnosis is made through DNA testing.
Fragile X syndrome is casued by a loss of FMR1 gene expression, which affects many different proteins in the brain. There is no known cure for FXS, but current research is looking to improve treatment options for affected individuals and their families.There are a few theories that may lead to new treatment in FXS. Our lab has pursued two of these.
Recent research has focused on the glutamate mGluR5 receptor. Research in FXS animal models shows excessive signaling downstream of the mGluR5 receptor. Improvement in brain function and behavior is seen when this signaling is decreased, either by manipulating the gene or by using medication to block the receptor. Medications that tune down the mGluR5 receptor are now being tested in adults, adolescents, and now children with Fragile X Syndrome in the hope that the same benefits will be seen.
Other research shows abnormalities in the GABA system in animal models of Fragile X Syndrome. Improvements are seen when a particular receptor, GABA-B, is stimulated. Medications that stimulate the GABA-B receptor have been used to treat individuals with nerve and muscle problems and are now being evaluated to treat symptoms of Fragile X Syndrome.
Major depressive disorder (MDD) is a common and serious illness in children and adolescents. Epidemiological studies and clinical samples estimate the prevalence of MDD as approximately 1%-2% of prepubertal children, and between 3% and 8% of adolescents. By the ages of 10 to 15, girls appear to be more likely to experience depression than boys. MDD is commonly associated with feelings of worthlessness, low self-esteem, and thoughts of suicide and its psychosocial burden in the formative years can compromise the developmental process. Patients also experience difficulties with concentration and motivation, impairing functioning in this critical period. Each year as many as 20% of adolescents have suicidal ideation and 9% attempt suicide. Suicide is a leading cause of death in adolescents and is a major public health concern. A major risk factor for suicide in adolescents is major depression. MDD in children and adolescents can be chronic and recurrent. The mean length of pediatric depressive episodes is approximately 7 months, and in the course of a first episode, up to 40% of patients appear to recover without specific treatment. However, patients who do not recover appear to be at high risk of chronic depression, and those who do recover have high rates of recurrence and dysthymia.