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SHR Neuro Krebs Kardio Lipid

Thomas, MG; Crosier, M; Lindsay, S; Kumar, A; Thomas, S; Araki, M; Talbot, CJ; McLean, RJ; Surendran, M; Taylor, K; Leroy, BP; Moore, AT; Hunter, DG; Hertle, RW; Tarpey, P; Langmann, A; Lindner, S; Brandner, M; Gottlob, I.
The clinical and molecular genetic features of idiopathic infantile periodic alternating nystagmus.
Brain. 2011; 134(Pt 3):892-902 [OPEN ACCESS]
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Autor/innen der Med Uni Graz:
Brandner Martina
Langmann Andrea
Lindner Susanne
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Number of Figures: 5
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Abstract:
Periodic alternating nystagmus consists of involuntary oscillations of the eyes with cyclical changes of nystagmus direction. It can occur during infancy (e.g. idiopathic infantile periodic alternating nystagmus) or later in life. Acquired forms are often associated with cerebellar dysfunction arising due to instability of the optokinetic-vestibular systems. Idiopathic infantile periodic alternating nystagmus can be familial or occur in isolation; however, very little is known about the clinical characteristics, genetic aetiology and neural substrates involved. Five loci (NYS1-5) have been identified for idiopathic infantile nystagmus; three are autosomal (NYS2, NYS3 and NYS4) and two are X-chromosomal (NYS1 and NYS5). We previously identified the FRMD7 gene on chromosome Xq26 (NYS1 locus); mutations of FRMD7 are causative of idiopathic infantile nystagmus influencing neuronal outgrowth and development. It is unclear whether the periodic alternating nystagmus phenotype is linked to NYS1, NYS5 (Xp11.4-p11.3) or a separate locus. From a cohort of 31 X-linked families and 14 singletons (70 patients) with idiopathic infantile nystagmus we identified 10 families and one singleton (21 patients) with periodic alternating nystagmus of which we describe clinical phenotype, genetic aetiology and neural substrates involved. Periodic alternating nystagmus was not detected clinically but only on eye movement recordings. The cycle duration varied from 90 to 280 s. Optokinetic reflex was not detectable horizontally. Mutations of the FRMD7 gene were found in all 10 families and the singleton (including three novel mutations). Periodic alternating nystagmus was predominantly associated with missense mutations within the FERM domain. There was significant sibship clustering of the phenotype although in some families not all affected members had periodic alternating nystagmus. In situ hybridization studies during mid-late human embryonic stages in normal tissue showed restricted FRMD7 expression in neuronal tissue with strong hybridization signals within the afferent arms of the vestibulo-ocular reflex consisting of the otic vesicle, cranial nerve VIII and vestibular ganglia. Similarly within the afferent arm of the optokinetic reflex we showed expression in the developing neural retina and ventricular zone of the optic stalk. Strong FRMD7 expression was seen in rhombomeres 1 to 4, which give rise to the cerebellum and the common integrator site for both these reflexes (vestibular nuclei). Based on the expression and phenotypic data, we hypothesize that periodic alternating nystagmus arises from instability of the optokinetic-vestibular systems. This study shows for the first time that mutations in FRMD7 can cause idiopathic infantile periodic alternating nystagmus and may affect neuronal circuits that have been implicated in acquired forms.
Find related publications in this database (using NLM MeSH Indexing)
Brain - embryology
Cohort Studies -
Cytoskeletal Proteins - genetics
DNA Mutational Analysis -
Family Health -
Female -
Fetus -
Genetic Diseases, X-Linked - genetics
Humans -
Infant -
Infant, Newborn -
Magnetic Resonance Imaging -
Male -
Membrane Proteins - genetics
Mutation - genetics
Nystagmus, Optokinetic - genetics
Nystagmus, Pathologic - genetics
Oculomotor Muscles - physiopathology
Phenotype -
Reflex, Vestibulo-Ocular - genetics
Semicircular Canals - pathology

Find related publications in this database (Keywords)
periodic alternating nystagmus
FRMD7
optokinetic reflex
vestibulo-ocular reflex
in situ hybridization
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