BMJ Case Rep. 2026 Aug 28;19(8):e274952. doi: 10.1136/bcr-2026-274952.
ABSTRACT
Oculocutaneous albinism (OCA) is characterised by hypopigmentation of the skin, hair and eyes. Developmental delay is not a commonly reported feature in OCA. A female toddler was diagnosed with OCA, global developmental delay, hypotonia and congenital heart disease.Given the coexisting neurodevelopmental and cardiac abnormalities, chromosomal microarray (CMA) analysis was performed, which revealed a homozygous deletion at chromosome 11q14.3 involving the TYR, GRM5 and NOX4 genes. Parental segregation analysis using CMA demonstrated heterozygous deletions in both parents, with the proband's homozygous deletion resulting from overlapping parental deletions.To our knowledge, this is the first reported case of a large TYR gene deletion causing OCA, thereby expanding the mutational spectrum associated with the disorder. This case highlights the importance of detailed phenotyping and appropriate selection of genetic testing. Additionally, parental segregation analysis plays a crucial role in improving diagnostic accuracy and in understanding genotype-phenotype correlations.
PMID:42665298 | DOI:10.1136/bcr-2026-274952