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Novel UBR1 gene mutation in a patient with typical phenotype of Johanson-Blizzard syndrome
Gholam Hossein Fallahi1, Mozhgan Sabbaghian, Manijeh Khalili
1Department of Pediatrics, Pediatrics Center of Excellence, Children's Medical Center, Tehran University of Medical Sciences, Tehran, Iran.
Abstract:
Johanson-Blizzard syndrome is a rare autosomal recessive disorder, characterized by exocrine pancreatic deficiency and a wide range of other abnormalities. We present here an infant with failure to thrive, exocrine pancreatic deficiency, short stature and developmental delay, cutis aplasia on the scalp, aplasia of alae nasi, hypospadias, hypothyroidism, myxomatous mitral valve, and patent ductus arteriosus. Molecular studies revealed a novel homozygous nonsense mutation in exon 38 of the UBR1 gene, which confirmed the diagnosis of Johanson-Blizzard syndrome. It should be acknowledged that the combination of exocrine pancreatic insufficiency and nasal wing hypo-aplasia is pathognomonic for this syndrome. Prompt diagnosis and exact monitoring of the patients with JBS are required to avoid further complications.
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