A Novel Missense SNRNP200Mutation Associated With Autosomal Dominant Retinitis Pigmentosa In A Chinese Family

Objective:1. To establish standard paper and electronic records of clinical database andblood samples database to collect and preserve the genetic resources of retinitispigmentosa.2. To analyze the clinical and genetic features of a retinitis pigmentosa familynamed SC001and to find the pathogenic gene mutation.3. To master the principle and data analysis of next-generation sequencing(NGS).Methods:1. Collecting and preserving clinical resources of SC001family including signingthe informed consent, filling out RP questionnaire, drawing the pedigree.The subjectwere examined by visual acuity, color vision, intraocular pressure, angle, Lens, fundus,visual field and electroretinography (ERG). Analyzing the Phenotype and determiningthe mode of inheritance. Extracting genomic DNA from10ml peripheral blood,identificating and preserving genomic DNA in-80℃cryogenic refrigerator. Archivingthe original paper and electronic records.2. Twenty-two exons of eight adRP candidate genes, RHO, Peripherin/RDS,ROM1, NRL, CRX, FSCN2, GUCA1B and TOPORS were amplified by polymerasechain reaction (PCR) and Sanger sequencing.3. Exome of the proband was captured using exome sequencing and data analysiswas performed to exclude known genetic defects. Subsequently, candidate mutationswere validated in affected family members and100normal unaffected individuals usingSanger Sequencing.Results:1. The paper and electronic records of clinical database and blood samples database of SC001family was scientifically and standardly established which inaccordance with international and domestic genetic resources collection principle.2. No mutation was found in eight adRP candidate genes in the members ofSC001family, but five single nucleotide changes were detected in exons ofPeripherin/RDS.3. A novel missense mutation, c.2653C> G transition (p.Q885E), in exon20ofSNRNP200was identified and co-segregated with the disease phenotype. The mutationwas absent in100normal unaffected individuals. USH2A c.2750G>A and PDE6Bc.1415G>A were single nucleotide polymorphisms (SNPs). USH2A c.10246T>G andc.997T>C were false-positive sites.Conclusion:1. Establishment of clinical and blood samples database of RP was the basis forthe study of RP which ensured the resource standard, normative and continued. Itprovided perfect model to collect RP families and laid the foundation for follow-upresearch and epidemiological survey.2.The SC001family was autosomal dominant RP family. RHO,Peripherin/RDS,ROM1, NRL, CRX, FSCN2, GUCA1B and TOPORS were not thepathogenetic gene of SC001. The five changes of single nucleotide in RDS exons wereSNPs.3.The novel missense mutation, c.2653C> G transition in exon20of SNRNP200was the pathogenetic gene mutation of SC001family. Not only enriched the spectrum ofSNRNP200, but also was reported in the world firstly. USH2A c.2750G>Aand PDE6Bc.1415G>Awere new SNPs.