Molecular, Cellular and Genomics Biomedicine Research Group, Instituto de Investigación Sanitaria La Fe, Valencia, Spain; Unidad Mixta de Enfermedades raras IIS La Fe-Centro de Investigación Príncipe Felipe, Valencia, Spain; Biomedical Research Network for Rare Diseases, Hospital Universitario y Politécnico La Fe, Valencia, Spain.
Molecular, Cellular and Genomics Biomedicine Research Group, Instituto de Investigación Sanitaria La Fe, Valencia, Spain; Unidad Mixta de Enfermedades raras IIS La Fe-Centro de Investigación Príncipe Felipe, Valencia, Spain; Biomedical Research Network for Rare Diseases, Hospital Universitario y Politécnico La Fe, Valencia, Spain; Genetics Unit, Hospital Universitario y Politécnico La Fe, Valencia, Spain.
J Mol Diagn. 2020 Apr;22(4):532-543. doi: 10.1016/j.jmoldx.2020.01.003. Epub 2020 Feb 7.
A cohort of 172 patients diagnosed clinically with nonsyndromic retinal dystrophies, from 110 families underwent full ophthalmologic examination, including retinal imaging, electrophysiology, and optical coherence tomography, when feasible. Molecular analysis was performed using targeted next-generation sequencing (NGS). Variants were filtered and prioritized according to the minimum allele frequency, and finally classified according to the American College of Medical Genetics and Genomics guidelines. Multiplex ligation-dependent probe amplification and array comparative genomic hybridization were performed to validate copy number variations identified by NGS. The diagnostic yield of this study was 62% of studied families. Thirty novel mutations were identified. The study found phenotypic intra- and interfamilial variability in families with mutations in C1QTNF5, CERKL, and PROM1; biallelic mutations in PDE6B in a unilateral retinitis pigmentosa patient; interocular asymmetry RP in 50% of the symptomatic RPGR-mutated females; the first case with possible digenism between CNGA1 and CNGB1; and a ROM1 duplication in two unrelated retinitis pigmentosa families. Ten unrelated cases were reclassified. This study highlights the clinical utility of targeted NGS for nonsyndromic inherited retinal dystrophy cases and the importance of full ophthalmologic examination, which allows new genotype-phenotype associations and expands the knowledge of this group of disorders. Identifying the cause of disease is essential to improve patient management, provide accurate genetic counseling, and take advantage of gene therapy-based treatments.
172 名临床诊断为非综合征性视网膜营养不良的患者队列，来自 110 个家庭，当可行时，接受了全面的眼科检查，包括视网膜成像、电生理学和光学相干断层扫描。使用靶向下一代测序（NGS）进行分子分析。根据最小等位基因频率对变体进行过滤和优先级排序，最后根据美国医学遗传学与基因组学学院的指南进行分类。进行多重连接依赖性探针扩增和阵列比较基因组杂交，以验证 NGS 鉴定的拷贝数变异。本研究的诊断率为 62%的研究家庭。鉴定出 30 个新突变。该研究发现，C1QTNF5、CERKL 和 PROM1 突变的家庭中存在表型的个体内和家族内变异性；单侧色素性视网膜炎患者中 PDE6B 的双等位基因突变；50%有症状的 RPGR 突变女性中存在双眼不对称性 RP；首例可能在 CNGA1 和 CNGB1 之间存在二倍体的病例；以及两个无关的色素性视网膜炎家庭中存在 ROM1 重复。重新分类了 10 个无关病例。本研究强调了靶向 NGS 在非综合征性遗传性视网膜营养不良病例中的临床应用，以及全面眼科检查的重要性，这允许新的基因型-表型关联，并扩展了该组疾病的知识。确定疾病的原因对于改善患者管理、提供准确的遗传咨询和利用基于基因治疗的治疗方法至关重要。
