Rare Behavioral Disorders

The most common rare behavioral disorders

Rare behavioral disorders are those rare disease which are defined by the presence of behavioral issues in individuals. 

Behavioral issues usually involve behavior that deviates from what is considered normal behavior. Generally to be classed as abnormal, this behavior must include more than one behavioral issue, last for longer than six months, and be noticed in a variety of different settings and environments. 

Specific behavioral disorders include oppositional defiant disorder, conduct disorder, and attention deficit hyperactivity disorder.

Rare behavioral disorders are rare diseases, or genetic syndromes, which include behavioral issues amongst their symptoms. They are often first diagnosed in childhood, and some of them are recognized as common genetic disorders in children also. 


Angelman syndrome

Angelman is a rare genetic syndrome that affects an individual’s development, and specifically their ability to walk. Individuals with Angelman experience different kinds of behavioral issues, including difficulty sleeping, as well as frequent laughing and smiling. Very few people with Angelman develop the ability to speak.

Pitt-Hopkins syndrome

As a behavioral disorder, Pitt-Hopkins shares similar symptoms with Angelman syndrome. Behavioral issues with this syndrome are common and widely recognized as a main symptom, and many individuals with this genetic condition do not develop the ability to speak. Intellectual disability and developmental delay are also common. 

Lujan Fryns syndrome

Lujan-Fryns presents with some serious and severe behavioral issues. These specifically include hyperactivity, aggression, intense shyness and social anxiety. At the same time attention-seeking behaviors are also common with the syndrome. Some individuals with this behavioral disorder are also diagnosed with autism spectrum disorder, which in turn can make it difficult for them to communicate and socialize with others. In some instances affected individuals experience hallucinations and delusions. 

Cri-du-chat syndrome

This rare behavioral disorder is known for its behavioral issues. The most common of these include self-injurious behavior, which is any behavior in which an individual intentionally hurts themselves. Examples of this include biting oneself, hitting oneself with an object, or hitting oneself against another object. 

Rett syndrome

This rare behavioral disorder occurs almost exclusively in girls, with males affected rarely surviving past infancy due to the severity of their symptoms. Symptoms and behavioral issues related to this syndrome are severe and tend to get worse with time. Behavioral issues include autistic-like behaviors, including repetitive hand movements, and difficulties with communication. 

Glass syndrome

This rare behavioral disorder includes behavioral issues such as hyperactivity, and aggressive tendencies in affected individuals. Individuals with this genetic condition often have an over-friendly personality, despite the aggressive tendencies. Intellectual disability and limited-zero speech development also characterize this genetic syndrome. 

Rare behavioral disorders are characterized by the complexity of their symptoms, and the similarities between sets of symptoms with each condition can complicate the genetic diagnosis process. 

For an accurate and timely diagnosis, genetic counselors are invaluable in placing an individual’s behavioral issues within the context of a rare disease. Based on these symptoms they are able to recommend specific genetic tests, and are able to provide important knowledge about each of these rare behavioral disorders, and provide insight into what life with each might look like.  

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