Clinical characteristics and candidate gene mutational screening in children with cone and cone-rod dystrophy
- VernacularTitle:小儿视锥细胞与视锥杆细胞营养不良的临床特点与候选基因突变分析
- Author:
Qingjiong ZHANG
;
Shiqiang LI
;
Xueshan XIAO
- Publication Type:Journal Article
- Keywords:
Cone(retina);
Rod(retina);
DNA mutational analysis;
Phenotype
- From:
Chinese Journal of Ocular Fundus Diseases
2000;0(04):-
- CountryChina
- Language:Chinese
-
Abstract:
Objective To analyze the clinical characteristics and to screen for causative mutations in CRX and GUCY2D genes in children with cone or cone-rod dystrophy. Methods Clinical data and genomic DNA was collected from 18 children with cone or cone-rod dystrophy, aged from 4 months to 8 years. The coding sequence of the cone-rod homeobox (CRX) gene and two exons of the retinal-specific guanylate cyclase GUCY2D gene (exons 2 and 8) were analyzed by using polymerase chain reaction(PCR) and heteroduplex combined with single-strand conformational polymorphism (heteroduplex-SSCP) analysis. Results All of the 18 patients manifested obvious visual impairment. Nystagmus, photophobia and mild ocular fundus changes were found in 13, 8,and 7 cases respectively. Normal fundus was seen in 11 cases. The visual acuity was less than 0.3 in 4 cases and was unable to measure in the other 14 cases because they were too young. Clinical ocular manifestations between cone and cone-rod dystrophy were overlapped. Mutation in the CRX and GUCY2D genes was not detected in the 18 children with cone and cone-rod dystrophy. Conclusion Visual impairment appeared more early and obvious than fundus changes in children with cone or cone-rod dystrophy. Mutation in the CRX gene may not contribute to this series of patients with cone and cone-rod dystrophy.
