A novel nonsense mutation of the GPR143 gene identified in a Chinese pedigree with ocular albinism.
BACKGROUND
The purpose of this study was to elucidate the molecular basis of ocular albinism type I in a Chinese pedigree.


RESULTS
Complete ophthalmologic examinations were performed on 4 patients, 7 carriers and 17 unaffected individuals in this five-generation family. All coding exons of four-point-one (4.1), ezrin, radixin, moesin (FERM) domain-containing 7 (FRMD7) and G protein-coupled receptor 143 (GPR143) genes were amplified by polymerase chain reaction (PCR), sequenced and compared with a reference database. Ocular albinism and nystagmus were found in all patients of this family. Macular hypoplasia was present in the patients including the proband. A novel nonsense hemizygous mutation c.807T>A in the GPR143 gene was identified in four patients and the heterozygous mutation was found in seven asymptomatic individuals. This mutation is a substitution of tyrosine for adenine which leads to a premature stop codon at position 269 (p.Y269X) of GPR143.


CONCLUSIONS
This is the first report that p.Y269X mutation of GPR143 gene is responsible for the pathogenesis of familial ocular albinism. These results expand the mutation spectrum of GPR143, and demonstrate the clinical characteristics of ocular albinism type I in Chinese population.
State Key Laboratory of Biotherapy, Ophthalmic Laboratories, Department of Ophthalmology, Translational Neuroscience Center, West China Hospital, Sichuan University, Chengdu, People's Republic of China.
Naihong
N
Yan
Xuan
X
Liao
Su-ping
SP
Cai
Changjun
C
Lan
Yun
Y
Wang
Xiaomin
X
Zhou
Yan
Y
Yin
Wenhan
W
Yu
Xuyang
X
Liu
D000328:Adult; D016117:Albinism, Ocular / Q000235:genetics*; D044466:Asian People; D018389:Codon, Nonsense / Q000235:genetics*; D003598:Cytoskeletal Proteins / Q000235:genetics; D005091:Exons / Q000235:genetics; D005136:Eye Proteins / Q000235:genetics*; D005260:Female; D006801:Humans; D008297:Male; D008562:Membrane Glycoproteins / Q000235:genetics*; D008565:Membrane Proteins / Q000235:genetics; D008875:Middle Aged; D010375:Pedigree; D016133:Polymerase Chain Reaction; D055815:Young Adult; D000099149:Ezrin
D018389:Codon, Nonsense; D003598:Cytoskeletal Proteins; D005136:Eye Proteins; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D000099149:Ezrin; C516168:FRMD7 protein, human; C095276:GPR143 protein, human; C071776:radixin