PCR primers for sanger sequencing in this study.

PurposeTo investigate the variants in 18 disease-causing genes associated with nonsyndromic myopia in 83 Chinese individuals diagnosed with early-onset high myopia(eo-HM).MethodsVariants in 18 candidate genes in 83 probands with eo-HM were distinguished by whole-exome sequencing (WES) and assessed by multistep bioinformatics analysis.ResultsFour likely pathogenic variants were detected in 4 of the 83 probands (4.8%) with eo-HM. All of these are missense variants, such as (NM_014452: c.443C > T) in TNFRSF21, (NM_013291: c.799C > G) in CPSF1, (NM_201269.3: c.3266A > G) in ZNF644, and (NM_001135195: c.577G > A) in SLC39A5. These variants were verified by Sanger sequencing, and all allele frequencies were less than 0.01 in the 1000G, ExAC, ESP6500, and gnomAD databases. In addition, the pathogenicity of these variants was determined using several computational tools including SIFT, Mutation Taster, Polyphen-2, PROVEAN, M-CAP, CADD, and DANN. However, it should be noted that the Tyr1089Cys variant was classified as neutral solely using PROVEAN.ConclusionOur findings support the hypothesis that the variants observed in TNFRSF21, CPSF1, ZNF644, and SLC39A5 are the causative genes of eo-HM and expand the spectrum of eo-HM variants observed across various ethnic groups. The dissemination of knowledge on the impact of TNFRSF21, CPSF1, ZNF644, and SLC39A5 on eo-HM is under investigation.