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International Foundation for Optic Nerve Disease

P. O. Box 777, Cornwall NY 12518, USA
Phone/Fax: (845) 5348606


 ^ X-(beta) cell X-cells are retinal ganglion cells described by their linear summation receptive field response. They are numerous and have rather narrow receptive fields as opposed to Y-cells



 ^ X Chromosome A sex determining chromosome. Alleles on X-chromosome loci may be partly responsible for Leber optic atrophy.


 ^ X-inactivation A process by which one of the two copies of the X chromosome present in female mammals is inactivated. Skewed X-inactivation has been suggested as an epigenetic mechanism influencing LHON penetrance. However, studies have not supported this hypothesis.

Gavin Hudson, Valerio Carelli, Rita Horvath, Massimo Zeviani, Hubert J. Smeets, Patrick F. Chinnery. X-Inactivation patterns in females harboring mtDNA mutations that cause Leber hereditary optic neuropathy. Mol Vis. 2007 Dec 21;13:2339-43 PMID 18199976


 ^ X-linked

Hudson G, Keers S, Yu Wai Man P, Griffiths P, Huoponen K, Savontaus ML, Nikoskelainen E, Zeviani M, Carrara F, Horvath R, Karcagi V, Spruijt L, de Coo IF, Smeets HJ, Chinnery PF. Identification of an X-chromosomal locus and haplotype modulating the phenotype of a mitochondrial DNA disorder. Am J Hum Genet. 2005 Dec;77(6):1086-91. Epub 2005 Oct 11. PMID 16380918


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