Abstract
Purpose: The purpose of this study is to describe the heterogeneous phenotype of individuals with an unusual type of albinism—minimal pigment oculocutaneous albinism. Methods: Nine patients with minimal pigment oculocutaneous albinism were identified and followed for up to 11 years. The criteria were the presence of oculocutaneous albinism in association with low hairbulb tyrosinase activity in the patient and disparate activity in the parents with one parent having normal activity and the other having low tyrosinase activity. Changes in skin, hair, and ocular pigment were followed as the patients matured. As a measure of ocular pigment, iris transillumination and macular transparency were graded according to a previously published scheme. Results: Patients were born with white scalp hair and skin, and nystagmus developed. Visual acuity was reduced to 20/50 to 20/200 for the group, but in one patient vision improved with maturity. Irides were blue. In seven patients, iris pigment developed, which was detected by transillumination with slit-lamp biomicroscopy, including the one patient with improved visual acuity. All patients had foveal hypoplasia, and melanin pigment in the fundi could not be detected by clinical examination. Visual acuity in the group did not correlate directly with the presence or development of iris transillumination or macular transparency. The pedigrees were consistent with an autosomal recessive inheritance pattern. Conclusion: This unique type of oculocutaneous albinism has heterogeneous clinical features. Minimal pigment oculocutaneous albinism appears to represent a new type of tyrosinase-related oculocutaneous albinism (OCA1MP).
Original language | English (US) |
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Pages (from-to) | 906-914 |
Number of pages | 9 |
Journal | Ophthalmology |
Volume | 101 |
Issue number | 5 |
DOIs | |
State | Published - 1994 |
Externally published | Yes |
Bibliographical note
Funding Information:Originally received: March I, 1993. Revision accepted: December 6, 1993. I Department of Ophthalmology, University of Minnesota, Minneapolis. 2 Department of Pediatrics, University of Minnesota, Minneapolis. 3 Department of Medicine, University of Minnesota, Minneapolis. 4 Institute of Human Genetics, University of Minnesota, Minneapolis. Presented in part as a poster at the American Academy of Ophthalmology Annual Meeting, Dallas, November 1992. Supported in part by grant GM 22167 (Dr. King), National Institutes of Health, Bethesda, Maryland, and an unrestricted grant from Research to Prevent Blindness, Inc, New York, New York (Dr. Summers).