Currently there is no cure for Rett syndrome. Treatment is directed towards improving function and addressing symptoms throughout life. A multi-disciplinary team approach is typically used to treat the person throughout life. This team may include primary care physician, physical therapist, occupational therapist, speech-language pathologist, nutritionist, and support services in academic and occupational settings.

Treatment of Rett syndrome includes:

Because of the increased risk of sudden cardiac death, when long QT syndrome is found on an annual screening EKG it is treated with an anti-arrhythmic such as a beta-blocker. There is some evidence that phenytoin may be more effective than a beta-blocker.

No cure is known for 22q11.2 deletion syndrome. Certain individual features are treatable using standard treatments. The key is to identify each of the associated features and manage each using the best available treatments.

For example, in children, it is important that the immune problems are identified early, as special precautions are required regarding blood transfusion and immunization with live vaccines. Thymus transplantation can be used to address absence of the thymus in the rare, so-called "complete" 22q11.2 deletion syndrome. Bacterial infections are treated with antibiotics. Cardiac surgery is often required for congenital heart abnormalities. Hypoparathyroidism causing hypocalcaemia often requires lifelong vitamin D and calcium supplements. Specialty clinics that provide multi-system care allow for individuals with 22q11.2 deletion syndrome to be evaluated for all of their health needs and allow for careful monitoring of the patients. An example of this type of system is the 22q Deletion Clinic at SickKids Hospital in Toronto, Canada, which provides children with 22q11 deletion syndrome ongoing support, medical care and information from a team of health care workers.

The main goals when treating children with autism are to lessen associated deficits and family distress, and to increase quality of life and functional independence. In general, higher IQs are correlated with greater responsiveness to treatment and improved treatment outcomes. No single treatment is best and treatment is typically tailored to the child's needs. Families and the educational system are the main resources for treatment. Studies of interventions have methodological problems that prevent definitive conclusions about efficacy, however the development of evidence-based interventions has advanced in recent years. Although many psychosocial interventions have some positive evidence, suggesting that some form of treatment is preferable to no treatment, the methodological quality of systematic reviews of these studies has generally been poor, their clinical results are mostly tentative, and there is little evidence for the relative effectiveness of treatment options. Intensive, sustained special education programs and behavior therapy early in life can help children acquire self-care, social, and job skills, and often improve functioning and decrease symptom severity and maladaptive behaviors; claims that intervention by around age three years is crucial are not substantiated. Available approaches include applied behavior analysis (ABA), developmental models, structured teaching, speech and language therapy, social skills therapy, and occupational therapy. Among these approaches, interventions either treat autistic features comprehensively, or focalize treatment on a specific area of deficit. There is some evidence that early intensive behavioral intervention (EIBI), an early intervention model based on ABA for 20 to 40 hours a week for multiple years, is an effective treatment for some children with ASD. Two theoretical frameworks outlined for early childhood intervention include applied behavioral analysis (ABA) and developmental social pragmatic models (DSP). One interventional strategy utilizes a parent training model, which teaches parents how to implement various ABA and DSP techniques, allowing for parents to disseminate interventions themselves. Various DSP programs have been developed to explicitly deliver intervention systems through at-home parent implementation. Despite the recent development of parent training models, these interventions have demonstrated effectiveness in numerous studies, being evaluated as a probable efficacious mode of treatment.

Many medications are used to treat ASD symptoms that interfere with integrating a child into home or school when behavioral treatment fails. More than half of US children diagnosed with ASD are prescribed psychoactive drugs or anticonvulsants, with the most common drug classes being antidepressants, stimulants, and antipsychotics. Antipsychotics, such as risperidone and aripiprazole, have been found to be useful for treating irritability, repetitive behavior, and sleeplessness that often occurs with autism, however their side effects must be weighed against their potential benefits, and people with autism may respond atypically. There is scant reliable research about the effectiveness or safety of drug treatments for adolescents and adults with ASD. No known medication relieves autism's core symptoms of social and communication impairments. Experiments in mice have reversed or reduced some symptoms related to autism by replacing or modulating gene function, suggesting the possibility of targeting therapies to specific rare mutations known to cause autism.

There is no known cure for autism, although those with Asperger syndrome and those who have autism and require little-to-no support are more likely to experience a lessening of symptoms over time. The main goals of treatment are to lessen associated deficits and family distress, and to increase quality of life and functional independence. In general, higher IQs are correlated with greater responsiveness to treatment and improved treatment outcomes. Although evidence-based interventions for autistic children vary in their methods, many adopt a psychoeducational approach to enhancing cognitive, communication, and social skills while minimizing problem behaviors. It has been argued that no single treatment is best and treatment is typically tailored to the child's needs.

Intensive, sustained special education programs and behavior therapy early in life can help children acquire self-care, social, and job skills. Available approaches include applied behavior analysis, developmental models, structured teaching, speech and language therapy, social skills therapy, and occupational therapy. Among these approaches, interventions either treat autistic features comprehensively, or focus treatment on a specific area of deficit. Generally, when educating those with autism, specific tactics may be used to effectively relay information to these individuals. Using as much social interaction as possible is key in targeting the inhibition autistic individuals experience concerning person-to-person contact. Additionally, research has shown that employing semantic groupings, which involves assigning words to typical conceptual categories, can be benevficial in fostering learning.

There has been increasing attention to the development of evidence-based interventions for young children with ASD. Two theoretical frameworks outlined for early childhood intervention include applied behavioral analysis (ABA) and the developmental social-pragmatic model (DSP). Although ABA therapy has a strong evidence base, particularly in regard to early intensive home-based therapy. ABA's effectiveness may be limited by diagnostic severity and IQ of the person affected by ASD. The Journal of Clinical Child and Adolescent Psychology has deemed two early childhood interventions as “well-established”: individual comprehensive ABA, and focused teacher-implemented ABA combined with DSP.

Another evidence-based intervention that has demonstrated efficacy is a parent training model, which teaches parents how to implement various ABA and DSP techniques themselves. Various DSP programs have been developed to explicitly deliver intervention systems through at-home parent implementation.

A multitude of unresearched alternative therapies have also been implemented. Many have resulted in harm to autistic people and should not be employed unless proven to be safe.

In October 2015, the American Academy of Pediatrics (AAP) proposed new evidence-based recommendations for early interventions in ASD for children under 3. These recommendations emphasize early involvement with both developmental and behavioral methods, support by and for parents and caregivers, and a focus on both the core and associated symptoms of ASD.

Neonatal seizures are often controlled with phenobarbital administration. Recurrent seizures later in life are treated in the standard ways (covered in the main epilepsy article). Depending on the severity, some infants are sent home with heart and oxygen monitors that are hooked to the child with stick on electrodes to signal any seizure activity. Once a month the monitor readings are downloaded into a central location for the doctor to be able to read at a future date. This monitor is only kept as a safeguard as usually the medication wards off any seizures. Once the child is weaned off the phenobarbital, the monitor is no longer necessary.

Surgery is typically used to correct structural heart defects and syndactyly. Propanolol or beta-adrenergic blockers are often prescribed as well as insertion of a pacemaker to maintain proper heart rhythm. With the characterization of Timothy syndrome mutations indicating that they cause defects in calcium currents, it has been suggested that calcium channel blockers may be effective as a therapeutic agent.

Males with pathogenic "MECP2" mutations usually die within the first 2 years from severe encephalopathy, unless they have an extra X chromosome (often described as Klinefelter syndrome), or have somatic mosaicism.

Male fetuses with the disorder rarely survive to term. Because the disease-causing gene is located on the X chromosome, a female born with an MECP2 mutation on her X chromosome has another X chromosome with an ostensibly normal copy of the same gene, while a male with the mutation on his X chromosome has no other X chromosome, only a Y chromosome; thus, he has no normal gene. Without a normal gene to provide normal proteins in addition to the abnormal proteins caused by a MECP2 mutation, the XY karyotype male fetus is unable to slow the development of the disease, hence the failure of many male fetuses with a MECP2 mutation to survive to term.

Females with a MECP2 mutation, however, have a non-mutant chromosome that provides them enough normal protein to survive longer. Research shows that males with Rett syndrome may result from Klinefelter's syndrome, in which the male has an XXY karyotype. Thus, a non-mutant "MECP2" gene is necessary for a Rett's-affected embryo to survive in most cases, and the embryo, male or female, must have another X chromosome.

There have, however, been several cases of 46,XY karyotype males with a MECP2 mutation (associated with classical Rett syndrome in females) carried to term, who were affected by neonatal encephalopathy and died before 2 years of age. The incidence of Rett syndrome in males is unknown, partly owing to the low survival of male fetuses with the Rett syndrome-associated MECP2 mutations, and partly to differences between signs caused by MECP2 mutations and those caused by Rett's.

Females can live up to 40 years or more. Laboratory studies on Rett syndrome may show abnormalities such as:

- EEG abnormalities from 2 years of age

- atypical brain glycolipids

- elevated CSF levels of "beta"-endorphin and glutamate

- reduction of substance P

- decreased levels of CSF nerve growth factors

A high proportion of deaths are abrupt, but most have no identifiable cause; in some instances death is the result most likely of:

- spontaneous brainstem dysfunction

- cardiac arrest, likely due to long QT syndrome, ventricular tachycardia or other arrhythmias

- seizures

- gastric perforation

Currently there is no specific treatment for this condition. Management is supportive.

Medications are used to address certain behavioral problems; therapy for children with PDD should be specialized according to the child's specific needs.

Some children with PDD benefit from specialized classrooms in which the class size is small and instruction is given on a one-to-one basis. Others function well in standard special education classes or regular classes with support. Early intervention, including appropriate and specialized educational programs and support services, play a critical role in improving the outcome of individuals with PDD.

The treatment of genetic disorders is an ongoing battle with over 1800 gene therapy clinical trials having been completed, are ongoing, or have been approved worldwide. Despite this, most treatment options revolve around treating the symptoms of the disorders in an attempt to improve patient quality of life.

Gene therapy refers to a form of treatment where a healthy gene is introduced to a patient. This should alleviate the defect caused by a faulty gene or slow the progression of disease. A major obstacle has been the delivery of genes to the appropriate cell, tissue, and organ affected by the disorder. How does one introduce a gene into the potentially trillions of cells which carry the defective copy? This question has been the roadblock between understanding the genetic disorder and correcting the genetic disorder.

There is no known cure for microcephaly. Treatment is symptomatic and supportive.

Given the benign nature of the condition and the low seizure frequency, treatment is often unnecessary. If treatment is warranted or preferred by the child and his or her family, antiepileptic drugs can usually control the seizures easily. Carbamazepine is the most frequently used first-line drug, but many other antiepileptic drugs, including valproate, phenytoin, gabapentin, levetiracetam and sultiame have been found effective as well. Bedtime dosing is advised by some. Treatment can be short and drugs can almost certainly be discontinued after two years without seizures and with normal EEG findings, perhaps even earlier.

Parental education about Rolandic epilepsy is the cornerstone of correct management. The traumatizing, sometimes long-lasting effect on parents is significant.

It is unclear if there are any benefits to clobazam over other seizure medications.

There is no known "cure" for PDD-NOS, but there are interventions that can have a positive influence. Early and intensive implementation of evidence-based practices and interventions are generally believed to improve outcomes. Most of these are individualized special education strategies rather than medical or pharmaceutical treatment; the best outcomes are achieved when a team approach among supporting individuals is utilized.

Some of the more common therapies and services include:

- Visual and environmental supports, visual schedules

- Applied behavior analysis

- Discrete trial instruction (part of applied behavior analysis)

- Social stories and comic strip conversations

- Physical and occupational therapy

As with other neuroleptic-induced tardive syndromes, there is no definite treatment for tardive dysphrenia. The continuing to take the drug or changing the dosage of the atypical antipsychotic drug in use, or augmenting it with a typical antipsychotic, can alleviate symptoms temporarily. However, these solutions carry the risk of worsening or perpetuating the iatrogenesis in the long term.

Some patients could gradually benefit from changing to a dopamine D2 receptor partial agonist agent like clozapine. These drugs do not induce up-regulation, instead acting as a prophylactic.

The signs and symptoms of 22q11.2 deletion syndrome are so varied that different groupings of its features were once regarded as separate conditions. These original classifications included velocardiofacial syndrome, Shprintzen syndrome, DiGeorge sequence/syndrome, Sedlackova syndrome, and conotruncal anomaly face syndrome. All are now understood to be presentations of a single syndrome.

ICD-10 2015 version mentions 22q11.2DS using two codes: D82.1 (Di George syndrome) and Q93.81 (Velo-cardio-facial syndrome). The ICD-11 Beta Draft discusses the syndrome under “LD50.P1 CATCH 22 phenotype". However, since this syndrome is caused by the deletion of a small piece of chromosome 22, it is recommended that the name "22q11.2 deletion syndrome (22q11.2DS)" be used.

Not all genetic disorders directly result in death, however there are no known cures for genetic disorders. Many genetic disorders affect stages of development such as Down syndrome. While others result in purely physical symptoms such as muscular dystrophy. Other disorders, such as Huntington's disease show no signs until adulthood. During the active time of a genetic disorder, patients mostly rely on maintaining or slowing the degradation of quality of life and maintain patient autonomy. This includes physical therapy, pain management, and may include a selection of alternative medicine programs.

Brain MRI shows vermis atrophy or hypoplasic. Cerebral and cerebellar atrophy with white matter changes in some cases.

In terms of the treatment for ativated PI3K delta syndrome, generally primary immunodeficiencies see the following used:

- Bacterial infection should be treated rapidly(with antibiotics)

- Antiviral therapy

- Modify lifestyle(exposure to pathogens need to be minimized)

Regressive autism occurs when a child appears to develop typically but then starts to lose speech and social skills, typically between the ages of 15 and 30 months, and is subsequently diagnosed with autism. Other terms used to describe regression in children with autism are autism with regression, autistic regression, setback-type autism, and acquired autistic syndrome. There is no standard definition for regression, and the prevalence of regression varies depending on the definition used. Some children show a mixture of features, with some early delays and some later losses; and there is evidence of a continuous spectrum of behaviors, rather than a black-and-white distinction, between autism with and without regression. According to the definitions in the DSM-5 the term "regressive autism" can refer to any type of autism spectrum disorder that involves regression, including Childhood Disintegrative Disorder.

MECP2 Duplication Syndrome (M2DS) is a rare disease that is characterized by severe intellectual disability and impaired motor function. It is an X-linked genetic disorder caused by the overexpression of MeCP2 protein.

M2DS was first described in 1999.

In a Nature article published on November 25, 2015, it was revealed that researchers at the Baylor College of Medicine, led by Dr. Huda Y. Zoghbi, have reversed MECP2 Duplication Syndrome in adult symptomatic mice using antisense therapy. Mice treated with an experimental ASO administered through the central nervous system had a reduction of MECP2 protein to normal levels and symptoms of hypoactivity, anxiety, and abnormal social behavior were resolved. Additionally, the seizure activity of the mice and abnormal EEG discharges were abolished. Initial studies demonstrated that reducing the MECP2 protein levels to the correct amount also normalized the expression of the other genes controlled by the MECP2 protein.

Regression in autism spectrum disorders is well documented; attribution of regression to environmental stress factors may result in a delay in diagnosis. The apparent onset of regressive autism is surprising and distressing to parents, who often initially suspect severe hearing loss. A controversy occurred following a fraudulent study linking MMR vaccine to autism, but since then, studies have shown no connection between autism and the MMR vaccine. There are also studies being done to test if certain types of regressive autism have an autoimmune basis.

The prognosis for patients diagnosed with Timothy syndrome is very poor. Of 17 children analyzed in one study, 10 died at an average age of 2.5 years. Of those that did survive, 3 were diagnosed with autism, one with an autism spectrum disorder, and the last had severe delays in language development. One patient with atypical Timothy syndrome was largely normal with the exception of heart arrhythmia. Likewise, the mother of two Timothy syndrome patients also carried the mutation but lacked any obvious phenotype. In both of these cases, however, the lack of severity of the disorder was due to mosaicism.

Autism spectrum, also known as autism spectrum disorder (ASD), is a range of conditions classified as neurodevelopmental disorders in the DSM-5. Individuals diagnosed with autism spectrum disorder present with two types of symptoms: problems in social communication and social interaction, and restricted, repetitive patterns of behavior, interests or activities.

The DSM-5 redefined the autism spectrum disorders to encompass the previous (DSM-IV-TR) diagnoses of autism, Asperger syndrome, pervasive developmental disorder not otherwise specified (PDD-NOS), and childhood disintegrative disorder.