There have been 30 cases of Marden-Walker Syndrome reported since 1966. The first case of this was in 1966 a female infant was diagnosed with blepharophimosis, joint contractures, arachnodactyly and growth development delay. She ended up passing at 3 months due to pneumonia.

Treatments are usually based on the individuals symptoms that are displayed. The seizures are controlled with anticonvulsant medication. For the behavior problems, the doctors proscribe to a few medications and behavioral modification routines that involve therapists and other types of therapy. Even if mental retardation is severe, it does not seem to shorten the lifespan of the patient or to get worse with age.

No specific treatment is available. Management is only supportive and preventive.

Those who are diagnosed with the disease often die within the first few months of life. Almost all children with the disease die by the age of three.

Treatment for MSS is symptomatic and supportive including physical and occupational therapy, speech therapy, and special education. Cataracts must be removed when vision is impaired, generally in the first decade of life. Hormone replacement therapy is needed if hypogonadism is present.

Treatment for this condition entails surveillance of growth and contractures. Furthermore the following are treatment options:

- Thyroid hormone replacement

- Speech therapy

- Hearing aids

The only treatment for MWS is only symptomatic, with multidisciplinary management

The recurrence of DOOR in siblings and the finding of DOOR syndrome in a few families with consanguinity suggest that the condition is an autosomal recessive genetic condition. Mutations in TBC1D24 have been identified in 9 families.

Unfortunately, there is not one specific treatment option that can rid a person of this syndrome. However, there are many routes one can take to make living with this disease a lot easier. For example, there are many treatment programs that doctors can specialize for patients and their needs. Meeting with a doctor is very crucial and these specializations can be very useful. Also, one can seek help from pediatricians, EENT doctors, audiologists, and orthopedists. Brace fittings, hearing aids, and physical therapy can also be pushed by one's doctor, so that a patient can live normally. Additionally, anticonvulsant drugs can be used to stop seizures.

Hennekam syndrome also known as intestinal lymphagiectasia–lymphedema–mental retardation syndrome, is an autosomal recessive disorder consisting of intestinal lymphangiectasia, facial anomalies, peripheral lymphedema, and mild to moderate levels of growth and intellectual disability.

It is also known as "lymphedema-lymphangiectasia-mental retardation syndrome".

In a subset of patients it is associated with CCBE1 according research published by its namesake, Raoul Hennekam. Other causal mutations were found in the FAT4 gene. Previously, mutations in the FAT4 gene had been only associated with van Maldergem syndrome. The molecular mechanism of the lymphedema phenotype in CCBE1-associated cases was identified as a diminished ability of the mutated CCBE1 to accelerate and focus the activation of the primary lymphangiogenic growth factor VEGF-C.

In terms of treatment/management for those with Mulibrey nanism should have routine medical follow-ups, additionally the following can be done:

- Growth hormone treatment

- Regular pelvic exams

- Pericardiectomy

In 2011, it was demonstrated that "de novo" mutations in the gene KAT6B caused YSS.

Treatment usually involves plastic and reconstructive surgery. Surgery may be needed to correct undescended testes or hernias.

On September 15, 1991 in Sydney, Australia at the Prince of Wales Children's Hospital, reported on two brothers with a distinct facial appearance, severe mental retardation, short stature, cryptorchidism (undescended testicle), asplenia in one (absent spleen), dramatic failure to thrive, early hypotonia, and later hypertonia, all suggestive of the Smith–Fineman–Myers syndrome. All five of the reported cases have been males, suggesting X-linked inheritance.

On September 23, 1998 at the Hospital Injury Research and Rehabilitation at the University of São Paulo in Bauru, Brazil report on two boys, monozygotic twins born to normal and non consanguineous parents, presenting with an unusual facial appearance, cortical atrophy, dolichocephaly, short stature, cleft palate, micrognathia, prominent upper central incisors, bilateral Sidney line, minor foot deformities, unstableness in walking, early hypotonia, hyperreflexia, hyperactivity, psychomotor retardation, and severe delay in language development. These symptoms resemble those previously described in the Smith–Fineman–Myers syndrome.

One case of Cohen Syndrome, in a Palestinian boy from Tul-Karem, was reported in the Israeli monthly Kol Israel BeAsakim (in Hebrew) in the December 2007 issue. Over the past several years there have been approximately 50 new cases worldwide. There are population groups with this condition in Australia, the UK and the US. It still seems to go undiagnosed leaving the number of cases less than 500.

There is currently no cure for GAPO syndrome, but some options are available to reduce the symptoms. Nearsightedness, which affects some sufferers of the disease, can be treated by corrective lenses. Unfortunately, optic atrophy as a result of degradation of the optic nerve (common with GAPO syndrome) cannot be corrected. Corticosteroids have been proposed as a treatment for optic nerve atrophy, but their effectiveness is disputed, and no steroid based treatments are currently available.

Marinesco–Sjögren syndrome (MSS), sometimes spelled Marinescu–Sjögren syndrome, is a rare autosomal recessive disorder.

DOOR (deafness, onychdystrophy, osteodystrophy, and mental retardation) syndrome is a genetic disease which is inherited in an autosomal recessive fashion. DOOR syndrome is characterized by mental retardation, sensorineural deafness, abnormal nails and phalanges of the hands and feet, and variable seizures. A similar deafness-onychodystrophy syndrome is transmitted as an autosomal dominant trait and has no mental retardation. Some authors have proposed that it may be the same as Eronen Syndrome, but since both disorders are extremely rare it is hard to make a determination.

Many of the congenital malformations found with Malpuech syndrome can be corrected surgically. These include cleft lip and palate, omphalocele, urogenital and craniofacial abnormalities, skeletal deformities such as a caudal appendage or scoliosis, and hernias of the umbillicus. The primary area of concern for these procedures applied to a neonate with congenital disorders including Malpuech syndrome regards the logistics of anesthesia. Methods like tracheal intubation for management of the airway during general anesthesia can be hampered by the even smaller, or maldeveloped mouth of the infant. For regional anesthesia, methods like spinal blocking are more difficult where scoliosis is present. In a 2010 report by Kiernan et al., a four-year-old girl with Malpuech syndrome was being prepared for an unrelated tonsillectomy and adenoidectomy. While undergoing intubation, insertion of a laryngoscope, needed to identify the airway for the placement of the endotracheal tube, was made troublesome by the presence of micrognathia attributed to the syndrome. After replacement with a laryngoscope of adjusted size, intubation proceeded normally. Successful general anesthesia followed.

A rare follow-up of a male with Malpuech syndrome was presented by Priolo et al. (2007). Born at term from an uneventful pregnancy and delivery, the infant underwent a surgical repair of a cleft lip and palate. No problems were reported with the procedure. A heart abnormality, atrial septal defect, was also apparent but required no intervention. At age three years, mental retardation, hyperactivity and obsessive compulsive disorder were diagnosed; hearing impairment was diagnosed at age six, managed with the use of hearing aids. Over the course of the decade that followed, a number of psychiatric evaluations were performed. At age 14, he exhibited a fear of physical contact; at age 15, he experienced a severe psychotic episode, characterized by agitation and a loss of sociosexual inhibition. This array of symptoms were treated pharmocologically (with prescription medications). He maintained a low level of mental deficiency by age 17, with moments of compulsive echolalia.

VLDLR-associated cerebellar hypoplasia (VLDLRCH; alternative names: dysequilibrium syndrome, DES; nonprogressive cerebellar disorder with mental retardation) is a rare autosomal recessive condition caused by a disruption of the VLDLR gene. First described as a form of cerebral palsy in the 1970s, it is associated with parental consanguinity and is found in secluded communities, with a number of cases described in Hutterite families.

Worldwide, it has been documented in 110 persons, 85 of them Finnish. It is a recessive genetic disease. Many people with Mulibrey nanism have parents who are closely related, consanguine. Signs and symptoms are variable, siblings who suffer this disease sometimes do not share the same symptoms.

Cohen syndrome (also known as Pepper syndrome or Cervenka syndrome, named after Michael Cohen, William Pepper and Jaroslav Cervenka, who researched the illness) is a genetic disorder.

First reported from Saudi Arabia in 1988, Sanjad-Sakati syndrome, also known as "Hypoparathyroidism-Retardation-Dysmorphism (HRD) syndrome", or less commonly as the "Middle East syndrome", is a very rare genetically inherited disorder seen in the Middle East and children of Middle Eastern origin elsewhere in the world.The condition is named after Sami A. Sanjad and Nadia Awni Sakati.

In most cases, between the age of 2 and 4 oculomotor signals are present. Between the age of 2 and 8, telangiectasias appears. Usually by the age of 10 the child needs a wheel chair. Individuals with autosomal recessive cerebellum ataxia usually survive till their 20s; in some cases individuals have survived till their 40s or 50s.

This disorder is caused by an abnormality of the TBCE gene, the locus for which is on Chromosome 1q42.3. The locus is a 230 kb region of gene with identified deletions and mutations in affected individuals. There are rare cases of the disorder not being due to a TBCE gene abnormality.

While many cases of HPMRS are caused by mutations in the PIGV gene, there may be genetic heterogeneity in the spectrum of Mabry syndrome as a whole. PIGV is a member of the molecular pathway that synthesizes the glycosylphosphatidylinositol anchor. The loss in PIGV activity results in a reduced anchoring of alkaline phosphatase to the surface membrane and an elevated alkaline phosphatase activity in the serum.