American Journal of Medical Genetics 110:353–358 (2002) Clinical Report Unbalanced Translocation (3;5)(q26.1;p14): A Clinical Report Massimiliano Rossi, 1 Pasqua Di Micco, 1 Lucia Perone, 1 Daniele De Brasi, 1 Vito Guzzetta, 1 Maria Vittoria Andreucci, 1 Giovanna Roberta Vega, 1 Maria Grazia Marzano, 1 Emilia Iaccarino, 2 and Generoso Andria 1 * 1 Department of Pediatrics, Federico II University, Naples, Italy 2 Santobono-Pausilipon Hospital, Naples, Italy A patient with a multiple congenital anoma- lies/mental retardation (MCA/MR) syndrome had an unbalanced translocation (3;5) (q26.1;p14), causing partial 5p monosomy and partial 3q trisomy. The phenotype observed in this patient results from the combination of those described in the iso- lated dup(3q) and del(5p) syndromes. Some clinical features of this patient are shared by the Smith-Lemli-Opitz syndrome (SLOS), a well-known MCA/MR syndrome due to the deficiency of 7-dehydrocholesterol reduc- tase (DHCR7). We review the previously reported cases of chromosomal anomalies with clinical features suggesting SLOS. ß 2002 Wiley-Liss, Inc. KEY WORDS: deletion 5p; duplication 3q; Smith-Lemli-Opitzsyndrome chromosome anomalies INTRODUCTION Duplication 3q syndrome is characterized by mental retardation, failure to thrive, dysmorphic face, limb anomalies, and possible association with internal mal- formations. Cri-du-chat syndrome, associated with deletions involving the short arm of chromosome 5, is characterized by a typical neonatal mewing cry, psy- chomotor delay, microcephaly, craniofacial anomalies, possible presence of heart malformations, or other inter- nal anomalies. We describe a patient with a multiple congenital anomalies/mental retardation (MCA/MR) syndrome due to an unbalanced translocation causing partial 5p monosomy and partial 3q trisomy. The phenotype ob- served in this patient results from the combination of those described in the isolated del(5p) and dup(3q) syndromes. Some clinical features of the patients have also been reported in the Smith-Lemli-Opitz syndrome (SLOS). This MCA/MR syndrome is due to the deficiency of 7- dehydrocholesterol reductase (DHCR7), the enzyme that catalyzes the last step of cholesterol biosynthesis. SLOS patients typically show low levels of cholesterol and abnormally high levels of 7-dehydrocholesterol (7-DHC) in biological fluids [Tint et al., 1994]. After the biochemical defect was first demonstrated, some patients with clinical features resembling SLOS, but without the typical biochemical anomalies, were repor- ted [Guzzetta et al., 1996; Kelley and Hennekam, 2000]. We review the literature for the previously reported cases of chromosomal anomalies with clinical features suggesting SLOS. CLINICAL REPORT The patient, a male, was born at term by breech presentation to healthy nonconsanguineous parents. Pregnancy and family history were unremarkable. Kar- yotyping of amniotic fluid cells performed during preg- nancy was reported to be normal. His birth weight was 3,150 g. He developed neonatal cholestatic hepatitis, with total bilirubin levels of 15 mg/ dl at 20 days of age, resolving spontaneously in the following months. During the first months of life the patient showed feeding difficulties, severe failure to thrive, recurrent infections, developmental delay, and generalized hypotonia. A standard karyotype was reported to be normal. At 10 months of age his length was 57 cm (< 5th centile), his weight was 4,350 g (< 5th centile), and his head circumference was 37 cm (< 5th centile). He also had a narrow forehead, hirsutism, epicanthal folds, *Correspondence to: Prof. Generoso Andria, Department of Pediatrics, Federico II University, Via Pansini 5, 80131 Naples, Italy. E-mail: andria@unina.it Received 18 April 2001; Accepted 10 February 2002 DOI 10.1002/ajmg.10440 ß 2002 Wiley-Liss, Inc.