Smith-Lemli-Opitz Syndrome

Also known as: Si, SLOS, SLO Syndrome, RSH Syndrome.

What is Smith-Lemli-Opitz Syndrome?

Smith-Lemli-Opitz syndrome is a genetic disorder that presents with slow growth before and after birth and multiple anomalies at birth.

What causes Smith-Lemli-Opitz Syndrome? 

SLOS is a genetic condition caused by inheritance of two non-working copies of an autosomal recessive gene (one copy inherited from each parent) that reduces the amount of an important enzyme (7- dehydrocholesterol reductase) preventing normal cholesterol metabolism. The severity of the disorder can vary between affected babies even in the same family. Once a couple has one child with SLOS, each subsequent pregnancy has a 25% chance for having SLOS.

What are the symptoms of Smith-Lemli-Opitz Syndrome?

Slow growth, a small head, intellectual disability, heart defects, extra fingers and toes (polydactyly), second and third toes joined together (syndactyly), cleft palate, underdeveloped external genitalia in boys are typical features. Other features include drooping eyes, abnormal gums and other different facial abnormalities. Other problems can include poor muscle tone (hypotonia), seizures, bowel obstruction, narrowing of the stomach outlet (pyloric stenosis) and sensitivity to light (photosensitivity).

What are Smith-Lemli-Opitz Syndrome care options?

There is no cure for Opitz syndrome. Particular symptoms and complications are treated individually as they arise.


Reviewed by: Mislen S Bauer, MD

This page was last updated on: July 06, 2021 03:45 PM

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