title: Use of genome-wide SNP homozygosity mapping in small pedigrees to identify new mutations in VSX2 causing recessive microphthalmia and a semidominant inner retinal dystrophy.
abstract: Mutations in the visual system homeobox 2 gene (VSX2, also known as CHX10), which encodes a retinal transcription factor from the paired homeobox family, have been implicated in recessive isolated microphthalmia. In this study, we use genome-wide single nucleotide polymorphism homozygosity mapping in unrelated small consanguineous pedigrees and a candidate gene approach to identify three further causative VSX2 mutations (two novel and one previously reported). All affected individuals with homozygous mutations had bilateral anophthalmia or severe microphthalmia with absent vision. In addition, we identified a novel inner retinal dystrophy in two carrier parents suggesting a semidominant effect for this particular VSX2 mutation. A further study of individuals with retinal degenerative conditions may reveal a causative role for heterozygous mutations in VSX2.
authors.affiliation: Department of Physiology, Anatomy, and Genetics, University of Oxford, Le Gros Clark Building, South Parks Rd, Oxford, OX1 3QX, UK.
authors.forename: Sibel Ugur
authors.initials: SU
authors.lastname: Iseri
authors.forename: Alexander W
authors.initials: AW
authors.lastname: Wyatt
authors.forename: Gudrun
authors.initials: G
authors.lastname: Nürnberg
authors.forename: Christian
authors.initials: C
authors.lastname: Kluck
authors.forename: Peter
authors.initials: P
authors.lastname: Nürnberg
authors.forename: Graham E
authors.initials: GE
authors.lastname: Holder
authors.forename: Ed
authors.initials: E
authors.lastname: Blair
authors.forename: Alison
authors.initials: A
authors.lastname: Salt
authors.forename: Nicola K
authors.initials: NK
authors.lastname: Ragge
mesh_terms: D000328:Adult; D002648:Child; D003241:Consanguinity; D005799:Genes, Dominant; D005808:Genes, Recessive; D018398:Homeodomain Proteins / Q000235:genetics*; D006720:Homozygote; D006801:Humans; D008850:Microphthalmos / Q000235:genetics*; D009154:Mutation; D010375:Pedigree; D020641:Polymorphism, Single Nucleotide; D012162:Retinal Degeneration / Q000235:genetics*; D014157:Transcription Factors / Q000235:genetics*
chemical_list: D018398:Homeodomain Proteins; D014157:Transcription Factors; C490289:VSX2 protein, human