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X-linked juvenile retinoschisis (XLRS) is an inherited retinal disease caused by mutations in the RS1 gene, resulting in splitting of the retinal layers and visual disturbances. To provide insights on this disease in our cohort, genetic examination, clinical presentation, and functional analysis were performed. We observed three main RS1 mutations in our cohort of six unrelated patients: RS1-D126G, RS1-R209H, and RS1-R213W. The RS1-D126G mutation, exclusively reported in Thai patients so far, showed the highest prevalence. Phenotypically, the D126G mutation manifested early (0.3–4 years old), presenting as asymmetrical visual acuity and schisis. Functional analysis revealed that the molecular pathomechanism of D126G was the failure of protein secretion attributable to endoplasmic reticulum retention. The understanding of the genotype-phenotype relationship and the pathomechanisms of specific mutations in a particular population could immensely benefit the pipeline of personalised treatment design for XLRS. [ABSTRACT FROM AUTHOR]

Purpose: To validate Postnatal Growth and Retinopathy of Prematurity (G-ROP) criteria for Thai infants. Study design: A retrospective review of infants receiving ROP screening during 2009–2020. Methods: Baseline characteristics, clinical progression and final ROP outcomes were collected. G-ROP was applied to infants who met at least one of the following 6 criteria: birth weight (BW) below 1051 g, gestational age (GA) under 28 weeks, weight gain (WG) less than 120 g during postnatal day 10–19, WG less than 180 g during day 20–29, WG less than 170 g during day 30–39 and hydrocephalus. Results: A total of 684 infants (boys, 53.4%) were included. Median (IQR) BW was 1200 (960–1470) grams and median GA was 30 (28–32) weeks. Prevalence of ROP was 26.6%, with 28 (4.1%) having type 1, 19 (2.8%) type 2 and, 135 (19.7%) having other ROP. Treatment was performed in 26 infants (3.8%). Sensitivity of G-ROP to include type 1, 2 or treatment-requiring ROP cases was 100% with 36.9% specificity, excluding 235 (34.4%) cases of unnecessary screening. To adjust for our setting of initial eye examination at 4 weeks' postnatal date, the last 2 criteria of G-ROP were replaced by the occurrence of grade 3 or 4 intraventricular hemorrhage (IVH). This modified G-ROP criteria yielded 100% sensitivity, 42.5% specificity and excluded 271 (39.6%) cases of unnecessary screening. Conclusion: G-ROP criteria can be applied to our hospital setting. Occurrence of IVH grade 3 or 4 was proposed as an alternative in modified G-ROP criteria. [ABSTRACT FROM AUTHOR]

Retinitis pigmentosa (RP) affects 1:5000 individuals worldwide. Interestingly, variations in 271 RP-related genes are indicated to vary among populations. We aimed to evaluate the genetic prevalence and phenotypic profiles of Thai patients with RP. The clinical and whole exome sequencing data of 125 patients suggestive of inherited retinal diseases (IRD), particularly non-syndromic RP, were assessed. We found a total of 258 variants (63% of which remained unavailable in the ClinVar database) in 91 IRD-associated genes. Among the detected genes, the eyes shut homolog (EYS) gene showed the highest prevalence. We also provide insights into the genotypic, baseline, and follow-up clinical presentations of seven patients with disease-causing EYS variations. This study could provide comprehension of the prevalence of RP-related genes involved in the Asian population. It might also provide information to establish advanced and personalised therapy for RP in the Thai population. [ABSTRACT FROM AUTHOR]

Autoimmune retinopathy (AIR) is a rare immune-mediated inflammation of the retina. The autoantibodies against retinal proteins and glycolytic enzymes were reported to be involved in the pathogenesis. This retrospective cohort study assessed the antiretinal autoantibody profiles and their association with clinical outcomes of AIR patients in Thailand. We included 44 patients, 75% were females, with the overall median age of onset of 48 (17–74, IQR 40–55.5) years. Common clinical presentations were nyctalopia (65.9%), blurred vision (52.3%), constricted visual field (43.2%), and nonrecordable electroretinography (65.9%). Underlying malignancy and autoimmune diseases were found in 2 and 12 female patients, respectively. We found 41 autoantibodies, with anti-α-enolase (65.9%) showing the highest prevalence, followed by anti-CAII (43.2%), anti-aldolase (40.9%), and anti-GAPDH (36.4%). Anti-aldolase was associated with male gender (P = 0.012, OR 7.11, 95% CI 1.54–32.91). Anti-CAII showed significant association with age of onset (P = 0.025, 95% CI − 17.28 to − 1.24), while anti-α-enolase (P = 0.002, OR 4.37, 95% CI 1.83–10.37) and anti-GAPDH (P = 0.001, OR 1.87, 95% CI 1.32–2.64) were significantly associated with nonrecordable electroretinography. Association between the antibody profiles and clinical outcomes may be used to direct and adjust the treatment plans and provide insights in the pathogenesis of AIR. [ABSTRACT FROM AUTHOR]

Purpose: Achromatopsia (ACHM) is an autosomal recessive cone disorder characterized by pendular nystagmus, photophobia, reduced visual acuity, and partial or total absence of color vision. Mutations in six genes (CNGA3, CNGB3, GNAT2, PDE6C, PDE6H, and ATF6) have been reported in ACHM. There is no information on these disease-associated genes in Thai population. This study aimed to investigate the molecular and clinical characteristics in Thai patients with ACHM. Methods: Seven unrelated Thai patients with ACHM were recruited. Detailed ophthalmologic examination was performed. Polymerase chain reaction (PCR)-coupled single-strand conformation polymorphism (SSCP) screening followed by Sanger sequencing was used to identify sequence variants in all exons and splice junctions of three genes (CNGA3, CNGB3, and GNAT2). The pathogenicity of the detected variants was interpreted. Segregation analysis was performed to determine variant sharing in available family members. Results: Four patients displayed different SSCP migration patterns. Sequence analysis revealed a reported pathogenic and a novel disease-associated variant in the CNGA3 gene. For the CNGB3 gene, we found two novel disease-associated variants and a reported variant of uncertain significance (VUS). Segregation analysis confirmed that the variants identified in each patient were present in the heterozygous state in their corresponding family members, which was consistent with an autosomal recessive mode of inheritance. Conclusions: This study demonstrated the first molecular and clinical characterization of ACHM in Thai patients. The identification of disease-associated genes in a specific population leads to a personalized gene therapy benefiting those affected patients. [ABSTRACT FROM AUTHOR]

The article identifies the genetic mutations of the XLRS1 gene and describes the ocular phenotypes in two unrelated Thai patients with X-linked juvenile retinoschisis. Mutation screening identified two point mutations, with the first proband developing vitreous hemorrhage in both eyes and the second proband developing slightly blurred vision at age 10 years. The researchers detected foveal and peripheral schisis, and fundus examination revealed the presence of fine white dots at the macula. The probands showed eletronegative electroretinography (ERG).