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Behavior phenotype in the RSH/Smith-Lemli-Opitz syndrome
E Tierney1, N A Nwokoro, F D Porter
1Department of Psychiatry, Kennedy Krieger Institute, Baltimore, Maryland 21231, USA. tierney@kennedykrieger.org
American Journal of Medical Genetics
|February 27, 2001
Summary
Smith-Lemli-Opitz syndrome (SLOS) is a metabolic disorder linked to significant behavioral issues. Many individuals exhibit self-injury, sensory problems, and social deficits, with some meeting autism criteria.
Area of Science:
- Neurodevelopmental disorders
- Metabolic disorders
- Behavioral genetics
Background:
- Smith-Lemli-Opitz syndrome (SLOS) is a rare genetic metabolic disorder.
- Behavioral phenotypes in SLOS are not fully understood.
- Potential overlap between SLOS and autistic disorder warrants investigation.
Purpose of the Study:
- To characterize the behavioral phenotype of SLOS.
- To assess social and communication abilities, sensory hyperreactivity, and autistic disorder deficits in SLOS.
- To determine the prevalence of autistic disorder diagnostic criteria in SLOS.
Main Methods:
- Evaluation of 56 SLOS subjects (0.3–32.3 years) using age-dependent questionnaires and telephone interviews.
- Direct observation and caregiver interviews for 47 subjects.
- Assessment using Autism Diagnostic Interview-Revised (ADI-R) algorithm questions for 17 subjects.
Main Results:
- 89% of subjects reported a history of self-injury (e.g., self-biting, head-banging, opisthokinesis).
- 53% of evaluated subjects met diagnostic criteria for autistic disorder.
- Additional findings included sensory hyperreactivity, temperament dysregulation, sleep disturbances, and social/communication deficits.
Conclusions:
- SLOS presents a distinct behavioral phenotype with high rates of self-injury and sensory issues.
- A significant proportion of SLOS individuals meet criteria for autistic disorder, suggesting a link.
- SLOS is a metabolic disorder associated with autism and other behavioral characteristics, forming a diagnostically important behavioral disorder.
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