Smith-Lemli-Opitz syndrome: clinical and biochemical findings in Brazilian patients

• Published in: Genetics and molecular biology 2006, Vol.29 (3), p.429-436
• Main Authors: Scalco, Fernanda B., Otto, Paulo A., Brunetti, Iguatemy L., Cruzes, Vania M., Moretti-Ferreira, Danilo
• Format: Article
• Language: English
• Subjects: 7-dehydrocholesterol; BIOCHEMISTRY & MOLECULAR BIOLOGY; cholesterol metabolism; GENETICS & HEREDITY; Smith-Lemli-Opitz syndrome
• ISSN: 1415-4757; 1678-4685; 1415-4757; 1678-4685
• DOI: 10.1590/S1415-47572006000300003

Smith-Lemli-Opitz syndrome (SLOS) or RSH syndrome comprises multiple congenital anomalies and mental retardation. The underlying defect is a deficiency in the activity of Delta super(7)-sterol reductase, which decreases cholesterol and increases 7-dehydrocholesterol (7-DHC) levels. Our aim was to identify and evaluate the frequency of SLOS manifestations in a group of Brazilian patients. Based on our own data and those reported previously, we present a simple method that allows the estimation of probabilities favoring the diagnosis of SLOS. We evaluated 30 patients clinically and determined their plasma levels of cholesterol and 7-dehydrocholesterol. In 11 patients, the diagnosis was confirmed by ultraviolet spectrophotometry (UV). Of 19 patients with normal laboratory results, 17 showed a high probability favoring the diagnosis of SLOS. The most significant signs and symptoms observed in over 2/3 of the biochemically confirmed cases were mental retardation (10/11), delayed neuropsychomotor development (10/11), syndactyly of 2 super(nd)/3 super(rd) toes (10/11), and craniofacial anomalies including microcephaly (11/11), incompletely rotated ears (8/11), palpebral ptosis (10/11), anteverted nostrils (10/11), and micrognathia (9/11). Genital anomalies were found in all male patients (6/6).