Smith-Lemli-Opitz syndrome: a variable clinical and biochemical phenotype.

Abstract

We have reviewed all known UK cases of Smith-Lemli-Opitz syndrome. Among 49 cases with proven 7-dehydrocholesterol reductase deficiency, half had been terminated or had died in infancy. The minimum incidence is 1 in 60 000. The frequent occurrence of hypospadias may account for 71% of recognised cases being male. Important common features which emerged include short thumbs, severe photosensitivity, aggressive behaviour, and atrioventricular septal defect. The typical facial appearance becomes less obvious with age and 20% of cases did not have 2/3 toe syndactyly. Biochemical measurements of serum 7-dehydrocholesterol did not correlate with clinical severity.(7Med Genet 1998;35:558-565)

The genetics of autistic disorders and its clinical relevance: a review of the literature

“…The phenotype is variable with only rare symptoms or multiple congenital anomalies comprising cleft palate, cataracts, ptosis, hypospadias, syndactyly and a distinctive craniofacial appearance. 66 The most common malformation in large-scale studies was the syndactyly of toes 2 and 3; however, only present in about 80% of affected individuals. 66,67 Two studies have shown a high rate of AD in individuals with SLO, 65,68 especially in children with a start of cholesterol supplementation after age 5 years.…”

Autism as a disorder of neural information processing: directions for research and targets for therapy

“…Another genetic condition that shares autistic symptoms is Smith-Lemli-Opitz syndrome (SLOS), an autosomal recessive, multiple malformation/mental retardation syndrome [213] with an estimated incidence among individuals of European ancestry of one in 40,000 to one in 60,000 births [150,202,39,132], and a probable average carrier frequency of 1% [132]. Principal abnormalities include a characteristic facial appearance, microcephaly, hypotonia, postnatal growth retardation, 2-3 toe syndactyly, and hypogenitalism.…”

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

“…Genital anomalies (cryptorchidism, hypospadias) are reported in males. Other findings include: delayed global developmental progress with hypotonia and neuropsychomotor disturbances; pyloric stenosis; infection susceptibility during infancy; and various cardiac, renal, and pulmonary anomalies (Curry et al, 1987;Guzzeta et al, 1996;Cunnif et al, 1997;Ryan et al, 1998;KrajewskaWalasek et al, 1999;Nowaczyk and Waye, 2001;Haas and Kelley, 2001). …”

“…The incidence of SLOS is not known accurately; estimates range from 1:10,000 to 1:60,000 (Lowry and Yong, 1980;Ryan et al, 1998;Kelley, 2000;Kelley and Hennekan, 2000;Nowaczyck et al, 2001). This variation may be due to different criteria used in the evaluation of patients.…”