{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,17]],"date-time":"2026-08-17T14:54:12Z","timestamp":1786978452220,"version":"build-2736575974"},"reference-count":27,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2026,8,17]],"date-time":"2026-08-17T00:00:00Z","timestamp":1786924800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["82201206"],"award-info":[{"award-number":["82201206"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"award":["82201206"],"award-info":[{"award-number":["82201206"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100018634","name":"State Key Laboratory of Ophthalmology","doi-asserted-by":"publisher","award":["2025QNJS17"],"award-info":[{"award-number":["2025QNJS17"]}],"id":[{"id":"10.13039\/501100018634","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100018634","name":"State Key Laboratory of Ophthalmology","doi-asserted-by":"publisher","award":["2025QZLH06"],"award-info":[{"award-number":["2025QZLH06"]}],"id":[{"id":"10.13039\/501100018634","id-type":"DOI","asserted-by":"publisher"}]},{"award":["2025QNJS17"],"award-info":[{"award-number":["2025QNJS17"]}],"id":[{"id":"https:\/\/ror.org\/003mfbe21","id-type":"ROR","asserted-by":"publisher"}]},{"award":["2025QZLH06"],"award-info":[{"award-number":["2025QZLH06"]}],"id":[{"id":"https:\/\/ror.org\/003mfbe21","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100007162","name":"National Natural Science Foundation of Guangdong Province","doi-asserted-by":"publisher","award":["2025A1515011468"],"award-info":[{"award-number":["2025A1515011468"]}],"id":[{"id":"10.13039\/501100007162","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Genes"],"abstract":"<jats:p>Objectives: SLC45A2-related oculocutaneous albinism type 4 (OCA4) is a genetically defined subtype of albinism; however, its ocular phenotype remains incompletely characterized. This study aimed to describe the systemic, ophthalmic, and genetic features of patients with genetically confirmed SLC45A2-related OCA4. Methods: Ninety patients with clinically diagnosed albinism were enrolled and underwent genetic testing. Patients with genetically confirmed SLC45A2-related OCA4 were included for further analysis. Demographic information, systemic pigmentation features, ophthalmic findings, and SLC45A2 variants were analyzed. Results: Five unrelated patients with genetically confirmed SLC45A2-related OCA4 were included, aged 5\u201333 years. Best-corrected visual acuity ranged from 0.1 to 1.0 logMAR, and spherical equivalent refractive error varied widely from \u22127.25 to +7.63 D. All patients exhibited iris transillumination defects and moderate-to-severe fundus hypopigmentation, both graded 2\u20133. Foveal hypoplasia was universally present, ranging from grade 1 to grade 4, with three patients showing grade 4 hypoplasia. Genetic analysis revealed nine disease-associated alleles representing eight distinct SLC45A2 variants: seven missense variants and one splice-altering variant. One patient carried a homozygous variant, and four carried compound heterozygous variants. Three novel variants were identified: c.1459C&gt;G (p.Gln487Glu), c.137A&gt;G (p.Glu46Gly), and c.561A&gt;G. Conclusions: This study characterizes the ocular phenotype of SLC45A2-related OCA4, including iris transillumination defects, fundus hypopigmentation, and foveal hypoplasia of varying severity. Three novel SLC45A2 variants were identified, expanding the mutational spectrum of OCA4.<\/jats:p>","DOI":"10.3390\/genes17080963","type":"journal-article","created":{"date-parts":[[2026,8,17]],"date-time":"2026-08-17T13:42:17Z","timestamp":1786974137000},"page":"963","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Ocular Phenotypes and Novel SLC45A2 Variants in Patients with Oculocutaneous Albinism Type 4"],"prefix":"10.3390","volume":"17","author":[{"given":"Chonglin","family":"Chen","sequence":"first","affiliation":[{"name":"State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou 510060, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bingqi","family":"Wang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou 510060, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ye","family":"Zheng","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou 510060, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Junyi","family":"Liu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou 510060, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xinping","family":"Yu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou 510060, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"26","DOI":"10.1167\/iovs.64.12.26","article-title":"Ophthalmologic Phenotype\u2013Genotype Correlations in Patients With Oculocutaneous Albinism Followed in a Reference Center","volume":"64","author":"Seguy","year":"2023","journal-title":"Investig. 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