Albinism
Also known as: Hypopigmentation; Ocular Albinism; Oculo-cutaneous Albinism
Background
Albinism is a group of genetic disorders in which the affected individual has reduced or absent pigmentation (colouring to skin, hair and eyes). It is thought that about 1 in 20,000 people are affected with albinism. All ethnic groups and both genders appear to be affected by albinism, which presents in the neonatal period (the first 28 days of life).
Credits
Medical text written August 2006 by Contact a Family. Approved August 2006 by Miss Isabelle Russell-Eggitt FRCS FRCOphth. Last updated November 2010 by Miss Isabelle Russell-Eggitt FRCS FRCOphth, Consultant Ophthalmic Surgeon, Great Ormond Street Hospital, London, UK.
There are two main types of albinism:
Ocular albinism (OA)
Predominantly affects the eyes, with affected individuals often having only slightly lighter skin and hair colour than other family members and it usually leads to nystagmus (see entry). Many individuals may have been given a diagnosis of ‘idiopathic nystagmus’, meaning that the cause is unknown.
Oculo-cutaneous albinism (OCA)
Affects the eyes and skin to a very variable extent.
There are rare variants of OCA:
- Hermansky-Pudlak syndrome – this presents with easy bruising and affected individuals may have lung, bowel and bleeding features
- Chediak-Higashi syndrome – in which there is an increased susceptibility to infection and bleeding.
Most individuals with albinism do not have any associated health problems.
Albinism is caused when there is a fault in one of the many different genes that control the production of melanin and the development of the eye and vision pathways.
Diagnosis can be made by the observation of the characteristic features of the disorders. An ophthalmologist will be involved in identifying the ocular features (those related to the eyes). In some cases that are not obvious, especially if the individual has some pigmentation, the characteristic abnormalities of the visual system are confirmed by a visually evoked potential (VEP) test. This test shows a detailed record of electrical activity in the visual pathways to the brain. Genetic tests are not yet available except rarely on a research basis.
Treatment for albinism is symptomatic and aims to reduce the problems caused by the disorder. High sun protection factor (SPF) sunscreen, sun glasses and clothing to protect the skin can all be helpful.
A range of telescopic and microscopic optical devices can provide great improvement in visual acuity by spreading the features of the object being viewed over a larger area of the abnormal macula (the central part of the retina).
Inheritance patterns
Ocular albinism is X-linked or autosomal recessive. OCA is autosomal recessive. Genetic counselling should be sought by families who are affected by the condition.
Prenatal diagnosis
Not currently available.
Albinism Fellowship
Helpline: 01282 771 900
Email: support@albinism.org.uk
Website: www.albinism.org.uk
The Fellowship is a Registered Charity in Scotland No. SC009443. It provides information and support for people with albinism and their families in the United Kingdom and Ireland.
Group details last updated December 2014.