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GTR Home > Conditions/Phenotypes > Smith-Lemli-Opitz syndrome

Summary

Excerpted from the GeneReview: Smith-Lemli-Opitz Syndrome
Smith-Lemli-Opitz syndrome (SLOS) is a congenital multiple-anomaly / cognitive impairment syndrome caused by an abnormality in cholesterol metabolism resulting from deficiency of the enzyme 7-dehydrocholesterol (7-DHC) reductase. It is characterized by prenatal and postnatal growth restriction, microcephaly, moderate-to-severe intellectual disability, and multiple major and minor malformations. The malformations include distinctive facial features, cleft palate, cardiac defects, underdeveloped external genitalia in males, postaxial polydactyly, and 2-3 syndactyly of the toes. The clinical spectrum is wide; individuals with normal development and only minor malformations have been described.

Genes See tests for all associated and related genes

  • Also known as: SLOS, DHCR7
    Summary: 7-dehydrocholesterol reductase

Clinical features

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