title: Clinical and genetic characteristics of Leber congenital amaurosis with novel mutations in known genes based on a Chinese eastern coast Han population.
abstract: OBJECTIVE
  To study the genotype-phenotype characteristics of Leber congenital amaurosis (LCA) in the Chinese eastern coast Han population.
  
  
  METHODS
  Children with strictly defined LCA with novel mutations of known LCA genes identified by targeted next-generation sequencing (NGS) and a prediction of pathogenicity (in silico) were included in this study (2013-2015). Mutations were confirmed using Sanger sequencing and segregation analysis. The clinical findings were recorded, including visual function, refractive error, fundus changes, and electroretinograms (ERGs). Spectral-domain optical coherence tomography (SD-OCT) examination, fundus fluorescein angiography (FFA), and ultra-wide field scanning laser ophthalmoscopy (UWF SLO) were performed on children when available.
  
  
  RESULTS
  A total of 65 patients underwent NGS for mutation screening and 45 patients were identified as carrying known LCA genes. Of these, 36(80 %) children harbored novel mutations, and they were all from the eastern coast of China. A total of 50 novel variants were identified, which covered 15 known LCA genes. GUCY2D (17 %), CEP290 (14 %), NMNAT1 (14 %), AIPL1 (11 %) and RPGRIP1 (11 %) were the five most frequently mutated genes with novel mutations. A total of four (11 %) patients with AIPL1 mutations harbored the same novel mutated allele (c.C241T p.Q81X), which was homozygous in patients 1 and 2. Unusual manifestations were detected in patient 16 who had novel mutations in CRB1 with a dense proliferative membrane adhering to the posterior retina of the right eye with numerous fine glistening crystals spreading over the retina of both eyes. Ten (40 %) of the 25 available patients who underwent SD-OCT showed a normal macular appearance using fundus photography but an abnormal macular structure using OCT imaging, most of whom presented with a thickened fovea with maldevelopment of the inner and outer retinal laminae.
  
  
  CONCLUSIONS
  There may be a high frequency of AIPL1 novel mutations and a founder mutation of p.Q81X in the Chinese eastern coast Han population. Our findings of specific features in this population broaden the spectrum of novel mutations and the phenotype of LCA with ethnic and regional variations. Fundus multimodality imaging may help guide comprehensive assessments for patients with LCA.
authors.affiliation: Department of Ophthalmology, Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, 1665 Kong Jiang Road, Shanghai, 200092, China.
authors.forename: Shiyuan
authors.initials: S
authors.lastname: Wang
authors.affiliation: Department of Ophthalmology, Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, 1665 Kong Jiang Road, Shanghai, 200092, China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Department of Ophthalmology, Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, 1665 Kong Jiang Road, Shanghai, 200092, China.
authors.forename: Xiang
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Department of Ophthalmology, Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, 1665 Kong Jiang Road, Shanghai, 200092, China.
authors.forename: Zhaoyang
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Department of Ophthalmology, Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, 1665 Kong Jiang Road, Shanghai, 200092, China. zhaopeiquan@126.com.
authors.forename: Peiquan
authors.initials: P
authors.lastname: Zhao
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D002681:China / Q000453:epidemiology; D004252:DNA Mutational Analysis; D004596:Electroretinography; D005136:Eye Proteins / Q000235:genetics*; D005260:Female; D005451:Fluorescein Angiography; D005654:Fundus Oculi; D005838:Genotype; D006801:Humans; D015994:Incidence; D057130:Leber Congenital Amaurosis / Q000453:epidemiology / Q000235:genetics* / Q000378:metabolism; D008297:Male; D008565:Membrane Proteins / Q000235:genetics* / Q000378:metabolism; D009154:Mutation; D009419:Nerve Tissue Proteins / Q000235:genetics* / Q000378:metabolism; D010375:Pedigree; D010641:Phenotype; D012160:Retina / Q000473:pathology* / Q000503:physiopathology; D012189:Retrospective Studies; D041623:Tomography, Optical Coherence / Q000379:methods*
chemical_list: D005136:Eye Proteins; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins
keywords: Chinese; Genotype-phenotype; Leber congenital amaurosis (LCA); Multimodality imaging; Next-generation sequencing (NGS); Novel mutation