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 Nurse Practitioner 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
