Prospective Study of the Phenotypic and Mutational Spectrum of Ocular Albinism and Oculocutaneous Albinism

• Published in: Genes 2021-03, Vol.12 (4), p.508
• Main Authors: Chan, Hwei Wuen, Schiff, Elena R, Tailor, Vijay K, Malka, Samantha, Neveu, Magella M, Theodorou, Maria, Moosajee, Mariya
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Albinism; Albinism, Ocular - diagnosis; Albinism, Ocular - genetics; Albinism, Oculocutaneous - diagnosis; Albinism, Oculocutaneous - genetics; Biosynthesis; Chediak-Higashi syndrome; Child; Child, Preschool; Diagnosis, Differential; Enzymes; Female; Genes; Genetic screening; Genetic Testing - methods; Genomes; Hair; Heritability; Humans; Hypoplasia; Infant; Iris; Male; Metabolism; Mutation; Ocular albinism; Pedigree; Phenotype; Prospective Studies; Proteins; Skin; Whole genome sequencing; Whole Genome Sequencing - methods; Young Adult
• ISSN: 2073-4425; 2073-4425
• DOI: 10.3390/genes12040508

Albinism encompasses a group of hereditary disorders characterized by reduced or absent ocular pigment and variable skin and/or hair involvement, with syndromic forms such as Hermansky-Pudlak syndrome and Chédiak-Higashi syndrome. Autosomal recessive oculocutaneous albinism (OCA) is phenotypically and genetically heterogenous (associated with seven genes). X-linked ocular albinism (OA) is associated with only one gene, . We report the clinical and genetic outcomes of 44 patients, from 40 unrelated families of diverse ethnicities, with query albinism presenting to the ocular genetics service at Moorfields Eye Hospital NHS Foundation Trust between November 2017 and October 2019. Thirty-six were children (≤ 16 years) with a median age of 31 months (range 2-186), and eight adults with a median age of 33 years (range 17-39); 52.3% ( = 23) were male. Genetic testing using whole genome sequencing (WGS, = 9) or a targeted gene panel ( = 31) gave an overall diagnostic rate of 42.5% (44.4% (4/9) with WGS and 41.9% (13/31) with panel testing). Seventeen families had confirmed mutations in ( = 9), , ( = 4), ( = 1), ( = 1), ( = 1), and ( = 1). Molecular diagnosis of albinism remains challenging due to factors such as missing heritability. Differential diagnoses must include -associated foveal hypoplasia and syndromic forms of albinism.