{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T09:36:37Z","timestamp":1785404197703,"version":"3.56.0"},"reference-count":39,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2026,5,19]],"date-time":"2026-05-19T00:00:00Z","timestamp":1779148800000},"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":"crossref","award":["2025QNJS17"],"award-info":[{"award-number":["2025QNJS17"]}],"id":[{"id":"10.13039\/501100018634","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100018634","name":"State Key Laboratory of Ophthalmology","doi-asserted-by":"crossref","award":["2025QZLH06"],"award-info":[{"award-number":["2025QZLH06"]}],"id":[{"id":"10.13039\/501100018634","id-type":"DOI","asserted-by":"crossref"}]},{"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"}]},{"name":"National Natural Science Foundation of Guangdong Province, China","award":["2025A1515011468"],"award-info":[{"award-number":["2025A1515011468"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Genes"],"abstract":"<jats:p>Objectives: Oculocutaneous albinism (OCA), a group of inherited disorders characterized by deficient melanin synthesis, leads to hypopigmentation of the skin, hair, and eyes. OCA type 2 (OCA2) is caused by mutations in OCA2. This study aimed to characterize the comprehensive clinical and genetic spectrum of OCA2, and to identify the key ocular determinants of visual acuity. Methods: We enrolled 90 probands clinically diagnosed with albinism. Whole-exome sequencing and comprehensive ophthalmic examinations were performed. Results:\u00a0OCA2 was confirmed in 29 probands (32.2%). Visual impairment was distributed as mild\/no impairment (30.8%), moderate (53.8%), and severe\/blindness (15.4%). All patients exhibited nystagmus and photophobia. Ocular phenotype grading showed distinct distributions: iris translucency (n = 25) was 68% grade 3, 20% grade 2, 8% grade 1, and 4% grade 4; fundus hypopigmentation (n = 26) was 42.3% grade 1, 30.8% grade 2, and 26.9% grade 3; and foveal hypoplasia (n = 20) was 70% grade 4, 25% grade 3, and 5% grade 1. We identified 33 OCA2 variants (26 compound heterozygous and 3 homozygous), with missense variants accounting for 62.1% of alleles. Five variants were identified to be novel. The severity of foveal hypoplasia demonstrated a strong, statistically significant negative correlation with visual acuity (r = \u22120.71, p &lt; 0.001). Conclusions: OCA2 accounts for 32.2% of albinism cases, with moderate visual impairment being the most common (53.8%). Graded phenotyping demonstrated moderate-to-severe iris translucency (88%), mild fundus hypopigmentation (42.3%), and severe (grade 4) foveal hypoplasia (70%). The severity of foveal hypoplasia emerged as an important determinant of visual acuity.<\/jats:p>","DOI":"10.3390\/genes17050583","type":"journal-article","created":{"date-parts":[[2026,5,20]],"date-time":"2026-05-20T15:45:34Z","timestamp":1779291934000},"page":"583","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Clinical Manifestations and Genetic Spectrum of Oculocutaneous Albinism Type 2 in Chinese Patients"],"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":"Jun","family":"Li","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":"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":"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":[[2026,5,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1953","DOI":"10.1016\/j.ophtha.2018.08.003","article-title":"The Phenotypic Spectrum of Albinism","volume":"125","author":"Kruijt","year":"2018","journal-title":"Ophthalmology"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"101091","DOI":"10.1016\/j.preteyeres.2022.101091","article-title":"The retinal pigmentation pathway in human albinism: Not so black and white","volume":"91","author":"Bakker","year":"2022","journal-title":"Prog. 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