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Smith-Lemli-Opitz syndrome among Arabs.
M Al-Owain1, F Imtiaz, T Shuaib
1Department of Medical Genetics, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia. alowain@kfshrc.edu.sa
Clinical Genetics
|June 24, 2011
Summary
Smith-Lemli-Opitz syndrome (SLOS), a rare genetic disorder, was confirmed in five Arab patients. This study highlights the disorder
Area of Science:
- Biochemistry
- Genetics
- Rare Diseases
Background:
- Smith-Lemli-Opitz syndrome (SLOS) is an autosomal recessive disorder resulting from 3β-hydroxycholesterol Δ(7)-reductase deficiency.
- Early diagnosis and understanding of SLOS are crucial due to its variable presentation and potential for severe developmental impact.
Observation:
- A 10-year biochemical screening of 191 plasma samples identified five Arab patients with confirmed SLOS.
- These patients exhibited characteristic features including growth retardation, global developmental delay, dysmorphic features, and syndactyly, indicating moderate to severe forms of the disorder.
- One patient presented with a unique cardiovascular anomaly: cor triatriatum with significant obstruction of right pulmonary veins.
Findings:
- Gas chromatography-mass spectrometry (GC-MS) was utilized to measure plasma cholesterol and 7-dehydrocholesterol levels.
- Genetic analysis revealed two known mutations (N287K and R352Q) and one novel mutation (R352L) in the DHCR7 gene in the affected individuals.
- The study confirms SLOS as a rare but present condition within the Arab population.
Implications:
- This research enhances the understanding of SLOS prevalence and clinical spectrum in Arab populations.
- Identifying specific DHCR7 mutations contributes to genetic diagnostics and counseling for SLOS.
- The findings underscore the importance of biochemical and genetic screening for rare genetic disorders in diverse ethnic groups.
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