Snyder-Robinson Syndrome

By | June 10, 2022

Snyder -Robinson syndrome is a genetic disease. The disease is usually extremely rare in the population. The typical cardinal symptoms of the disease are mental retardation, difficulty walking, hypotonia of the muscles, osteoporosis and an often asymmetrical face.

What is Snyder-Robinson Syndrome?

Snyder-Robinson Syndrome was named after the two doctors who first described the disease. This first description was made in 1969 by Snyder and Robinson. In English, the disease is also referred to as spermine synthase deficiency. The disease is characterized by a spectrum of symptoms and signs, sometimes occurring in different combinations. For heatstroke explanations, please visit

In addition, the individual complaints often vary from patient to patient with regard to their severity. Basically, Snyder-Robinson syndrome is a very rare disease. Affected individuals are usually mentally retarded, have significant difficulty walking and running, and have comparatively brittle bones.

The affected patients are particularly susceptible to osteoporosis. The tone of the muscles is often not as pronounced as in healthy people, so that the sick people are comparatively weak. This fact is usually noticeable in childhood. Sometimes the people have what is known as kyphoscoliosis and show asymmetry in the facial area.


In principle, the Snyder-Robinson syndrome is a very rare, genetically determined disease. The prevalence of the disease is now estimated at less than 1:1,000,000. In addition, numerous studies of patients and their families indicate that the disease is inherited in the children in an x-linked recessive manner.

Basically, the cause of Snyder-Robinson syndrome can be found in genetic mutations. According to previous findings, these take place on the so-called SMS gene and here in particular on the gene locus Xp22.11. This gene segment is responsible for coding the so-called spermine synthase. Due to the mutation, spermine synthase disorders occur as part of the disease.

Symptoms, Ailments & Signs

Patients with Snyder-Robinson syndrome suffer from various complaints and symptoms. Depending on the individual case, these symptoms may vary in severity. The combination of different signs of the syndrome also varies in many cases among the people affected.

Basically, the sick patients have a so-called asthenic stature. Mental development is slowed down in the majority of cases. Many patients have a pronounced mental retardation. Many patients suffer from kyphoscoliosis as well as difficulty speaking. The affected persons often have significant anomalies, especially in the facial area.

For example, an asymmetry of the face is typical, as well as a conspicuous lower lip area. The osteoporosis associated with the disease makes sufferers particularly prone to fractures of bones. In addition, they often suffer from joint contractures.

Diagnosis & course of disease

Some of the characteristic symptoms of Snyder-Robinson syndrome appear immediately after birth or in early childhood. These include primarily the abnormalities in the facial area. Muscle weakness is also usually noticeable in small children and raises the suspicion of a hereditary disease, since the symptoms are present from birth.

During the anamnesis, the treating doctor clarifies the patient’s complaints, with the parents of the affected child playing a decisive role in the majority of cases. They inform the doctor about the onset and severity of the symptoms. The disease is diagnosed with the help of numerous methods of examination technology.

First of all, the doctor approaches the signs of the disease in the normal case in the context of visual examinations. The anomalies of the face, for example the typical asymmetry, are the focus of attention. Osteoporosis is diagnosed, among other things, with examinations of the density of the bones. Mental disabilities and delayed intellectual development are usually noticeable in early childhood and can be detected using various test methods.

The impairments of the joints can be diagnosed, for example, using X-ray examinations or other imaging methods. Overall, the characteristic association of symptoms points to Snyder-Robinson syndrome. A genetic test is usually used to diagnose the disease with a high degree of certainty. As a result, the responsible gene mutation can be detected at the known gene locus.

When making the diagnosis, the attending physician also conducts a differential diagnosis. The doctor differentiates the disease primarily from Rett syndrome and a glycerol kinase deficiency. In addition, a monoamine oxidase A deficiency and Prader-Willi syndrome must be ruled out.


As a rule, those affected by Snyder-Robinson syndrome suffer from a number of different complaints that can lead to significant restrictions and problems in everyday life. The patients usually suffer from a clearly delayed development. This also leads to severe limitations in adulthood and thus to mental retardation.

The children are often dependent on special support and on the help of other people in their everyday life. Significant complaints and complications also occur when speaking and communicating. Because of facial abnormalities and deformities, many children also suffer from bullying or teasing. This can also lead to psychological problems or depression.

Furthermore, those affected by Snyder-Robinson syndrome are very prone to fractures and can thus easily injure themselves. The joints are also often weak and the fingers can be overstretched very easily. As a rule, the Snyder-Robinson syndrome cannot be treated causally.

Those affected are dependent on various therapies in their lives, which can limit the symptoms. In many cases, the parents or relatives of the patients also suffer from severe psychological problems. However, the life expectancy of the patient is not reduced by the Snyder-Robinson syndrome.

When should you go to the doctor?

People with Snyder-Robinson syndrome are usually confronted with medical consultations immediately after birth because of this rare hereditary disease. However, only some of the typical symptoms are visible at this point. It is also possible that the first warning signs only become apparent in infancy. In this case, the first visits to the doctor will be later.

The Snyder-Robinson syndrome can be recognized by certain abnormalities and asymmetries in the face, as well as by a noticeable muscular weakness. The child’s parents should go to a specialist immediately if they have such signs, since in all probability it is a question of a serious disorder or illness of their small child. The precise observation and documentation of the abnormalities observed offers decisive information for the doctor consulted.

The specialist consulted will carry out various examinations to determine the cause of the presenting symptoms. These include, for example, visual findings, bone density measurements or special test procedures that prove a mental disability. X-rays can be used to document the joint impairments that are typical of Snyder-Robinson syndrome.

All in all, a clear picture emerges. This secures the diagnosis “Snyder-Robinson syndrome”. A genetic test can provide the final clue if there are still doubts. It is possible that the disease is confused with Rett syndrome, glycerol kinase deficiency, monoamine oxidase A deficiency or Prader-Willi syndrome. All have similar symptoms in visual findings.

Treatment & Therapy

The Snyder-Robinson syndrome has not yet been causally treatable, which is why only the symptoms of the disease are treated. The complaints are partially reduced by means of special care and support for the affected persons as well as the administration of suitable medicines.

With regard to the mental handicap, the people concerned usually receive tuition in a special school and special educational support. Various physiotherapeutic measures are also used in some patients.


The Snyder-Robinson syndrome is hereditary, which is why no effective prevention of the disease is currently possible or tested.


Follow-up care for Snyder-Robinson syndrome serves to identify typical complications at an early stage and to support the patient in everyday life. In addition, the therapy is adapted to the symptoms as part of the aftercare. Patients with Snyder-Robinson Syndrome need both physiotherapeutic follow-up care and mental support.

Typical complications that need to be clarified during follow-up care are broken bones or joint contractures as a result of osteoporosis. At regular intervals, a specialist must examine the stability of the bones. If necessary, physiotherapy is then prescribed. Follow-up care in the hospital is indicated after a surgical intervention, such as may be necessary to correct facial abnormalities.

Depending on the type of intervention, the patient must remain in the clinic for a few days or weeks. As part of the aftercare, the wound healing is checked and finally the result of the corrective operation is assessed. Patients with a pronounced asthenic physique also need comprehensive physiotherapy, which often lasts for years or decades.

Follow-up care is provided by the responsible specialist. This usually involves several specialists such as neurologists, chiropractors and orthopedists. Aftercare for Snyder-Robinson syndrome lasts a lifetime due to the pronounced symptoms. Individual symptoms can be treated in the long term, while others recur or can only be marginally alleviated by therapy.

You can do that yourself

If a diagnosed case of Snyder-Robinson syndrome is known within the family, couples should consult a doctor before planning offspring. This can be seen as helpful for clarifying the risk and assessing further developments.

The hereditary disease is associated with reduced mental performance. As a result, those affected are hardly or not at all able to take responsibility for self-help measures. For this reason, relatives and medical professionals are responsible for establishing an optimal design of the treatment plan and everyday life for the person concerned. In most cases, early intervention programs are carried out. Relatives can also independently carry out exercises and training units with the person concerned to improve general health development outside of the therapies.

It is important that family members know and respect their own limits when caring for the patient. Compensation for caring for the person concerned is important in order to avoid situations of excessive demands. A speech disorder is characteristic. Therefore, a very own communication should be established in everyday life. This helps to determine the wishes and needs of the patient. In addition, when dealing with everyday life, it is important to find a way of good exchange.

Snyder-Robinson Syndrome