Search

AimsTo assess the association of single-nucleotide polymorphisms (SNPs) with myopia progression for polygenic risk prediction in children.MethodsSix SNPs (ZC3H11Brs4373767, ZFHX1Brs13382811, KCNQ5rs7744813, METrs2073560, SNTB1rs7839488 and GJD2rs524952) were analysed in 1043 school children, who completed 3-year follow-up, using TaqMan genotyping assays. SNP associations with progression in spherical equivalent (SE) were analysed by logistic regression. Polygenic risk scores (PRS) were applied for computing the sum of the risk alleles of multiple SNPs corresponding to myopia progression, weighted by the effect sizes of corresponding SNPs.ResultsGJD2rs524952 showed significant association with fast progression (OR=1.32, 95% CI 1.10 to 1.59; p=0.003) and KCNQ5rs7744813 had nominal association (OR=1.32, 95% CI 1.04 to 1.67; p=0.02). In quantitative traits locus analysis, GJD2rs524952 and KCNQ5rs7744813 were associated with progression in SE (β=−0.038 D/year, p=0.008 and β=−0.042 D/year, p=0.02) and axial elongation (β=0.016 mm/year, p=0.01 and β=0.017 mm/year, p=0.027). ZFHX1Brs13382811 also showed nominal association with faster progression in SE (β=−0.041 D/year, p=0.02). PRS analysis showed that children with the highest PRS defined by rs13382811, rs7744813 and rs524952 had a 2.26-fold of increased risk of fast myopia progression (p=4.61×10−5). PRS was also significantly associated with SE progression (R2=1.6%, p=3.15×10−5) and axial elongation (R2=1.2%, p=2.6×10−4).ConclusionsIn this study, multi-tiered evidence suggested SNPs in ZFHX1B, KCNQ5and GJD2as risk factors for myopia progression in children. Additional attention and appropriate interventions should be given for myopic children with high-risk PRS as defined by GJD2rs524952, KCNQ5rs7744813 and ZFHX1Brs13382811.

ObjectiveTo investigate the associations of multiple single-nucleotide polymorphisms (SNPs) with the severities and endophenotypes of myopia in children.MethodsA total of 3300 children aged 5–10 years were recruited: 137 moderate and high myopia (SE≤−3.0D), 670 mild myopia (−3.0D−0.5D). 13 SNPs in 13 genes/loci were selected for genotyping in all subjects using TaqMan assays. Associations between each SNP with myopia severities and ocular traits (spherical equivalent (SE), axial length (AL) and corneal radius (CR)) were analysed.ResultsWhen compared with controls, SNPs ZC3H11Brs4373767 (OR=1.15, p=0.038), BICC1rs7084402 (OR=1.18, p=0.005) and GJD2rs524952 (OR=1.14, p=0.025) showed nominal associations with overall myopia. ZC3H11Brs4373767 and BICC1rs7084402 showed stronger associations with moderate and high myopia (rs4373767: OR=1.42, p=0.018; rs7084402: OR=1.33, p=0.025), while GJD2rs524952 had a stronger association with mild myopia (OR=1.14, p=0.025). GJD2rs524952 also showed a difference between emmetropia and hyperopia (p=0.018). In quantitative trait locus analysis, ZC3H11Brs4373767, KCNQ5rs7744813 and GJD2rs524952 were correlated with both myopic SE (β=−0.09, p=0.03; β=−0.12, p=0.007; β=−0.13, p=0.0006, respectively) and AL (β=0.07, p=0.002; β=0.09, p=0.0008; β=0.07, p=0.0003, respectively). SNTB1rs7839488 was correlated with both AL (β=0.07, p=0.005) and CR (β=0.02, p=0.006). Moreover, ZC3H11Brs4373767-T (β=0.006; p=0.018), KCNQ5rs7744813-A (β=0.007; p=0.015) and GJD2rs524952-T (β=0.009; p=0.0006) were correlated with AL-CR ratio.Conclusions and RelevanceZC3H11Band BICC1are genetic risk factors for moderate and high myopia, while ZC3H11B, KCNQ5, SNTB1and GJD2confer risk to excessive AL in children.

ObjectiveTo investigate the associations of single-nucleotide polymorphisms (SNPs) in the ZC3H11B, ZFHX1B, VIPR2, SNTB1and MIPEPgenes with severities of myopia in Chinese populations.MethodsBased on previous myopia genome-wide association studies, five SNPs (ZC3H11Brs4373767, ZFHX1Brs13382811, VIPR2rs2730260, SNTB1rs7839488 and MIPEPrs9318086) were selected for genotyping in a Chinese cohort of 2079 subjects: 252 extreme myopia, 277 high myopia, 393 moderate myopia, 366 mild myopia and 791 non-myopic controls. Genotyping was performed by TaqMan assays. Allelic frequencies of the SNPs were compared with myopia severities and ophthalmic biometric measurements.ResultsThe risk allele T of ZC3H11BSNP rs4373767 was significantly associated with high myopia (OR=1.39, p=0.007) and extreme myopia (OR=1.34, p=0.013) when compared with controls, whereas ZFHX1Brs13382811 (allele T, OR=1.33, p=0.018) and SNTB1rs7839488 (allele G, OR=1.71, p=8.44E-05) were significantly associated with extreme myopia only. In contrast, there was no significant association of these SNPs with moderate or mild myopia. When compared with mild myopia, subjects carrying T allele of rs4373767 had a risk of progressing to high myopia (spherical equivalent ≤−6 dioptres) (OR=1.29, p=0.017). Similarly, the T allele of rs13382811 also imposed a significant risk to high myopia (OR=1.36, p=0.007). In quantitative traits analysis, SNPs rs4373767, rs13382811 and rs7839488 were correlated with axial length and refractive errors.ConclusionsWe confirmed ZC3H11Bas a susceptibility gene for high and extreme myopia, and ZFHX1Band SNTBfor extreme myopia in Chinese populations. Instead of myopia onset, these three genes were more likely to impose risks of progressing to high and extreme myopia.

ObjectiveTo conduct a systematic review and meta-analysis of the association of blood vitamin D (25-hydroxyvitamin D, 25(OH)D) concentration and vitamin D pathway genes with myopia.MethodsWe searched the MEDLINE and EMBASE databases for studies published up to 29 January 2018. Cross-sectional or cohort studies which evaluated the blood 25(OH)D concentration, blood 25(OH)D3 concentration or vitamin D pathway genes, in relation to risk of myopia or refractive errors were included. Standard mean difference (SMD) of blood 25(OH)D concentrations between the myopia and non-myopia groups was calculated. The associations of blood 25(OH)D concentrations and polymorphisms in vitamin D pathway genes with myopia using summary ORs were evaluated.ResultsWe summarised seven studies involving 25 008 individuals in the meta-analysis. The myopia group had lower 25(OH)D concentration than the non-myopia group (SMD=−0.27 nmol/L, p=0.001). In the full analysis, the risk of myopia was inversely associated with blood 25(OH)D concentration after adjusting for sunlight exposure or time spent outdoors (adjusted odds ratio (AOR)=0.92 per 10 nmol/L, p<0.0001). However, the association was not statistically significant for the <18 years subgroup (AOR=0.91 per 10 nmol/L, p=0.13) and was significant only for 25(OH)D3 (likely to be mainly sunlight derived), but not total 25(OH)D (AOR=0.93 per 10 nmol/L, p=0.00007; AOR=0.91 per 10 nmol/L, p=0.15). We analysed four single nucleotide polymorphisms in the VDR gene from two studies; there was no significant association with myopia.ConclusionsLower 25(OH)D is associated with increased risk of myopia; the lack of a genetic association suggests that 25(OH)D level may be acting as a proxy for time outdoors.

ObjectiveTo investigate the associations between 16 single-nucleotide polymorphisms (SNPs) in 14 genetic loci and keratoconus in an independent Chinese cohort.MethodsThis cross-sectional, case-control association study included a Chinese cohort of 133 patients with keratoconus and 371 control subjects. In a recent meta-analysis study, we identified association of 16 SNPs in 14 gene loci with keratoconus. In this study, we genotyped these 16 SNPs in all the patients and controls and analysed their association with keratoconus, its clinical severities and progression profiles. We also analysed the genotype-phenotype correlation between individual SNPs and steep keratometry, flat keratometry (Kf), average keratometry (Avg K) and best-fit sphere diameter (BFS) of the anterior and posterior corneal surface.ResultsAmong the 16 selected SNPs, rs1324183 in the MPDZ-NF1Blocus showed a significant association with keratoconus (OR=2.22; 95% CI 1.42 to 3.45, p=4.30×10–4), especially severe keratoconus (OR=5.10, 95% CI 1.63 to 15.93, p=0.005). The rs1324183 A allele was positively associated with anterior Kf (p=0.008), anterior Avg K (p=0.017), posterior Kf (p=0.01) and negatively associated with apex pachymetry (p=0.007) and anterior BFS (p=0.023) in keratoconus. The other 15 SNPs had no significant association with keratoconus or genotype-phenotype correlations.ConclusionsThis study confirmed the association of SNP rs1324183 in MPDZ-NF1Bwith keratoconus and revealed the association of this SNP with keratoconus severity and corneal parameters. It is thus a putative genetic marker for monitoring the progression of keratoconus to a severe form and facilitating early intervention.

AimsTo investigate the association of the paired box gene 6(PAX6) with different severities of myopia.MethodsA total of four haplotype-tagging single-nucleotide polymorphisms (SNPs; rs2071754, rs3026354, rs3026390 and rs628224) and two previously reported SNPs (rs644242 and rs662702) in the PAX6gene were analysed in a Hong Kong Chinese cohort of 1288 myopia subjects (including 252 extreme myopia, 277 high myopia, 393 moderate myopia and 366 mild myopia) and 791 no myopia controls. Allelic association analyses were performed for individual SNPs in different subgroups of myopia and in combined myopia, followed by a meta-analysis of our current data with reported data on PAX6in myopia.ResultsThe association of tagging SNPs rs2071754 and rs644242 with extreme myopia could not withstand multiple correction (rs2071754: OR=1.25, P value=0.031; rs644242: OR=1.33, P value=0.032). In the meta-analysis, rs644242 showed an enhanced, significant association with extreme myopia (OR=1.27, 95% CI 1.10 to 1.46, P value=0.001; I2=0%). In contrast, there was no significant association between the PAX6SNPs and high, moderate or mild myopia. No linear correlation was found between the PAX6SNPs and axial length.ConclusionThis study provides additional evidence suggesting that the PAX6SNP rs644242 is associated with extreme myopia but not lower grade myopia. Thus, PAX6may be implicated in the development or progression into severe myopia. Further longitudinal studies are warranted.

The PAX6gene is among the most studied genes in high myopia, but reported findings of association studies on PAX6and high myopia are inconsistent. We conducted a systematic review and meta-analysis to evaluate the association of PAX6polymorphisms and high myopia.