title: TSEN54 gene-related pontocerebellar hypoplasia type 2 presenting with exaggerated startle response: report of two cases in a family.
abstract: The pontocerebellar hypoplasias (PCHs) are a heterogeneous group of autosomal recessive disorders characterized by hypoplasia of the ventral pons and cerebellum, with variable cerebral involvement and severe psychomotor retardation. Eight different subtypes (PCH1-8) have been reported up to now. PCH2 is the most common type, generally caused by homozygous mutations in the TSEN54 gene and characterized by cerebellar hypoplasia that affects the hemispheres more severely than the vermis, progressive cerebral atrophy, microcephaly, dyskinesia, seizures and death in early childhood. We present two cousins with PCH2. Both patients presented with exaggerated startle response in the newborn period. Here we discuss the clinical and neuroradiological findings of PCH2, and its differentiation from familial startle disease or hereditary hyperekplexia.
authors.affiliation: Division of Child Neurology, Department of Pediatrics, Kocaeli University Faculty of Medicine, Kocaeli, Turkey. hulyamaras@gmail.com.
authors.forename: Hülya
authors.initials: H
authors.lastname: Maraş-Genç
authors.forename: Emek
authors.initials: E
authors.lastname: Uyur-Yalçın
authors.forename: Rasim Özgür
authors.initials: RÖ
authors.lastname: Rosti
authors.forename: Joseph G
authors.initials: JG
authors.lastname: Gleeson
authors.forename: Bülent
authors.initials: B
authors.lastname: Kara
mesh_terms: D002531:Cerebellum / Q000002:abnormalities*; D002648:Child; D002658:Developmental Disabilities / Q000150:complications / Q000175:diagnosis / Q000235:genetics; D004722:Endoribonucleases / Q000235:genetics*; D005260:Female; D006720:Homozygote; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D009154:Mutation / Q000235:genetics; D009421:Nervous System Malformations / Q000150:complications / Q000175:diagnosis* / Q000235:genetics*; D009849:Olivopontocerebellar Atrophies / Q000150:complications / Q000175:diagnosis* / Q000235:genetics*; D010375:Pedigree; D013216:Reflex, Startle / Q000235:genetics*
chemical_list: D004722:Endoribonucleases; C559616:TSEN54 protein, human