Albinism
Summary
- Albinism is a hypopigmentation syndrome that results from tyrosinase deficiency – a failure to produce melanin.
Clinical Presentation
- Patients have white hair, pale eyes and skin (with increased risk of skin cancer from lack of protection against UV-light).
Key Tyrosine Disorders that Cause Pigmentation Abnormalities
- In phenylketonuria, patients have hypopigmentation due to a lack of melanin.
- In pheochromocytoma, patients have dark-pigmented tumors, due to the hyperpigmented nature of the catecholamine-secreting, tyrosine-derived tumor.
- In alkaptonuria, patients have dark urine due to tyrosine-based HGA excess.