Identification of two novel mutations in families with X-linked ocular albinism. Mol Vis 2007 Oct 02;13:1856-61
Date
10/26/2007Pubmed ID
17960122Scopus ID
2-s2.0-34948893453 (requires institutional sign-in at Scopus site) 4 CitationsAbstract
PURPOSE: Our goal was to evaluate the OA1 gene, also known as G-protein coupled receptor 143 (GPR143), in two United States families, one from the mid-west and one from the mid-south, who had clinical features of X-linked ocular albinism. Both families had previously tested negative for mutations.
METHODS: Selected family members underwent a detailed ophthalmologic evaluation. Blood samples were obtained, and genomic DNA isolated. Mutational analysis by direct sequencing was used to evaluate OA1 exons and intron/exon junction.
RESULTS: Ophthalmic features in the evaluated family members were consistent with X-linked ocular albinism. Mutation screening and sequence analysis of the OA1 gene in the mid-west family identified a novel 190delC deletion. The 190delC mutation was predicted to result in a frameshift following Ser63, an addition of 16 novel amino acids and a premature stop. In the mid-south family, a 346T>G substitution was identified in exon 2. The 346T>G mutation was predicted to result in a substitution of the highly conserved Cys116 to Gly and disruption of the disulfide bridge essential for the normal structure and function of the OA1 protein.
CONCLUSIONS: Two novel mutations in the OA1 gene were identified in two families with ocular albinism. The identified mutations are likely loss-of-function mutations. These findings confirm that mutations in the OA1 gene are associated with the majority of X-linked ocular albinism cases.
Author List
Iannaccone A, Gallaher KT, Buchholz J, Jennings BJ, Neitz M, Sidjanin DJAuthor
Danielle Sidjanin Maier PhD APP Inpatient 2 in the Medicine department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AdolescentAdult
Albinism, Ocular
Amino Acid Substitution
Cysteine
Eye Proteins
Female
Gene Deletion
Genetic Diseases, X-Linked
Glycine
Humans
Male
Membrane Glycoproteins
Mutation
Pedigree
Twins, Monozygotic
