Purpose.: To evaluate variants in the LRPAP1, CTSH, LEPREL1, ZNF644, SLC39A5, and SCO2 genes in 298 unrelated patients with early-onset high myopia (eoHM). Methods.: Genomic DNA from 298 patients with eoHM was analyzed by whole exome sequencing. Variants in LRPAP1, CTSH, LEPREL1, ZNF644, SLC39A5, and SCO2 genes were selected and analyzed with bioinformatics. Potential candidate variants were confirmed by Sanger sequencing and then validated in available family members and 192 healthy controls. Results.: A total of nine variants predicted to affect the functional residues were detected. The LRPAP1 gene showed a homozygous frameshift mutation (c.199delC, p.Q67Sfs*8) in a consanguineous family. The ZNF644 gene showed five heterozygous missense mutations (c.1106A>T, p.K369M; c.1648G>A, p.A550T; c.2014A>G, p.S672G; c.2048G>C, p.R683T, and c.2551G>C, p.D851H) in five families, but the c.1106A>T, (p.K369M) and c.1648G>A, (p.A550T) in ZNF644 did not co-segregated with high myopia in the families and should be excluded as causative mutations. The SLC39A5 gene showed a heterozygous missense variant (c.1238G>C, p.G413A) in a sporadic individual. The SCO2 gene showed two heterozygous missense variants (c.334C>T, p.R112W and c.358C>T, p.R120W) in two families. None of the variants was detected in 192 healthy controls and all were predicted to be damaging by both Polyphen-2 and SIFT, except for the previously reported p.S672G mutation in ZNF644, which was predicted to be damaging by SIFT but benign by Polyphen-2. No homozygous or compound heterozygous variants were found in CTSH and LEPREL1. Conclusions.: Our results provide additional evidence to support the idea that mutation in LRPAP1 is associated with high myopia. Further studies are expected to evaluate the pathogenicity of the variants in CTSH, LEPREL1, ZNF644, SLC39A5, and SCO2.

Purpose: To investigate mutations in 234 genes associated with retinal dystrophies in a cohort of 298 probands with early-onset high myopia using whole exome sequencing. Methods: Genomic DNA from 298 probands with early-onset high myopia was analyzed by whole exome sequencing. Variants from 234 genes were selected and analyzed by multistep bioinformatics analyses. Results: Systematic analysis of variants in the 234 genes identified potential pathogenic mutations in 34 of 234 genes in 71 of 298 (23.8%) probands. Of the 71 probands, 44 (62.0%) had mutations in 11 genes responsible for ocular diseases accompanied by high myopia, including COL2A1, COL11A1, PRPH2, FBN1, GNAT1, OPA1, PAX2, GUCY2D, TSPAN12, CACNA1F, and RPGR. Initial clinical records of the 71 patients with mutations did not show recognizable signs of original diseases other than high myopia. Conclusions: Mutations in genes known to be responsible for retinal diseases were found in approximately one-fourth of the probands with early-onset high myopia. The high mutation frequency of RetNet genes in these patients can provide clues for genetic screening and further specific clinical examinations of high myopia to promote long-term follow-up assessment and prompt treatment of some diseases.

Purpose: We evaluate the power of a next-generation sequencing-based ophthalmic targeted sequencing panel (NGS-based OTSP) as a genetics-testing tool for patients suspected of a wide range of hereditary eye diseases. Methods: NGS-based OTSP encompasses 126 genes with identified mutations that account for the majority of Chinese families with hereditary eye diseases. A total of 568 probands suspected of having hereditary eye diseases underwent genetic testing by OTSP with targeted phenotype-driven analysis. Results: NGS-based OTSP detected 329 potential pathogenic variants in 62 genes. These mutations might represent the genetic cause in 52% (293/568) of probands suspected of having hereditary eye diseases. Within the disease subgroups, the detection rates were 61% (124/202) for retinal degeneration disease, 53% (35/66) for eye tumors, 49% (53/108) for retinal vessel disease, 46% (13/28) for retinal detachment, 33% (19/58) for significant refractive error, 35% (16/46) for optic atrophy, 48% (11/23) for anterior segment dysgenesis, and 59% (22/37) for other hereditary eye diseases. These detection rates are comparable to those obtained in our previous study performed with whole exome sequencing. Mutations in the same gene were detected in different forms of hereditary eye diseases. The average turnaround time for OTSP is 30 days, and the average cost is 139 USD per patient. Conclusions: NGS-based OTSP is a powerful tool for routine clinical genetic diagnostic testing in patients suspected of having hereditary eye diseases. Translational Relevance: NGS-based OTSP can be used as a routine clinical test to improve the genetic counseling and medical care of patients suspected of having hereditary eye diseases. View Original Download Slide View Original Download Slide

Purpose.: Two recent large-scale genome-wide association studies identified significant associations between myopia and single nucleotide polymorphisms (SNPs) near the PRSS56, BMP3, KCNQ5, LAMA2, TOX, TJP2, RDH5, ZIC2, RASGRF1, GJD2, RBFOX1, and SHISA6 genes. Our study is to examine whether rare variants in these genes contribute to high myopia. Methods.: Whole-exome sequencing was performed on samples of 298 probands with early-onset high myopia (eoHM; spherical refraction in each meridian ≤ −6.00 [diopters] D in both eyes; age of onset < 7 years) and 195 controls (different forms of retinal degeneration including Leber congenital amaurosis, cone-rod dystrophy, and familial exudative vitroretinopathy). Potential variations in these genes were selected for further validation and comparison to the controls. Moreover, Sanger sequencing was used to evaluate the coding regions and the upstream 800 bps of GJD2 in 395 additional subjects with late-onset moderate to high myopia (loMHM; spherical refraction in each meridian ≤ −4.00 D; age of onset ≥ 7 years) and 403 healthy controls (−0.50 D ± 1.00 D). Results.: Exome sequencing of the 298 probands with eoHM identified 25 rare variants that were predicted to affect coding residues. The segregation analysis and the distribution of rare variants between patients and controls did not provide evidence to support their involvement in myopia. Sanger sequencing of GJD2 in an additional 395 subjects with loMHM and 403 healthy controls did not identify myopia-associated variants. Conclusions.: We did not find evidence to support the association of myopia with rare variants in these genes, probably due to our limited sample size. Additional studies are expected to validate these results.