Autism Spectrum Disorder

Autism in Cornelia de Lange Syndrome

The three core characteristics of Autism (also referred as Autism Spectrum Disorder in some medical manuals such as DSM-5 and ICD-11) include the following:

• Differences and difficulties in communication
• Problems or delays with social interaction
• The presence of restricted repetitive behaviours or interests

Studies have shown that characteristics associated with autism occur in many people with Cornelia de Lange syndrome.

People with Cornelia de Lange syndrome are more likely, than people with Cri du Chat syndrome (who have a comparable level of ability and receptive language skills), to reach the cut-off scores for autism on an observational assessment of characteristics associated with autism.  The diagnostic cut-off scores represent the level at which individuals diagnosed with autism are expected to score. Approximately 43% of people with Cornelia de Lange syndrome score on this assessment at a level that would be expected in individuals with autism.

This does not mean that all individuals with Cornelia de Lange syndrome should receive a diagnosis of autism.  Rather, it suggests that autistic-like characteristics are common in individuals with Cornelia de Lange syndrome.

Differences in communication

Impairments in communication are the most prominent autistic-like characteristic associated with Cornelia de Lange syndrome.  Research suggests that both verbal and nonverbal communication skills are compromised.

Differences in social interaction skills

People with Cornelia de Lange syndrome (CdLS) often exhibit differences in social interaction skills. These may include social anxiety, extreme shyness, and selective mutism (e.g., avoiding speaking in required situations like school), which can resemble autism. Research indicates that nearly half of individuals with CdLS display autistic traits, with social interaction differences being a key characteristic. As individuals with CdLS grow older and face increased social demands, the distinctions between social interaction patterns in CdLS and autism become more evident.

Restricted Repetitive Behaviours

Restricted repetitive behaviours are typical in CdLS, such as rocking, spinning, and flapping. Repetitive behaviours are a key feature of autism, although not everyone who displays these behaviours will meet criteria for a diagnosis of autism. More frequent repetitive behaviours in CdLS are associated with a more severe level of intellectual disability and autism.