Oculocutaneous albinism.
Oculocutaneous albinism.
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DOI：
10.1186/1750-1172-2-43
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发表时间：
2007-11-02
影响因子：
3.7
通讯作者：
中科院分区：
文献类型：
--
作者：
眼皮肤白化病（OCA）是一组遗传性黑色素生物合成障碍性疾病，其特征是头发、皮肤和眼睛的色素沉着普遍减少。所有形式的白化病的患病率在世界范围内差异很大，估计约为1/17，000，这表明约70人中有1人携带OCA基因。OCA的临床谱范围很广，OCA1A是最严重的类型，在整个生命中完全缺乏黑色素生成，而较温和的OCA1B，OCA2，OCA3和OCA4随着时间的推移显示出一些色素积累。临床表现为不同程度的先天性眼球震颤、虹膜色素减退和半透明、视网膜色素上皮细胞色素减少、中心凹发育不全、视力下降（20/60~20/400）、屈光不正、色觉障碍和明显的畏光症。视神经走错是一个特征性的发现，导致斜视和立体视觉降低。皮肤和毛发色素减退的程度因OCA的类型而异。皮肤癌的发病率可能会增加。所有四种类型的OCA都是常染色体隐性遗传疾病。至少有四种基因负责不同类型的疾病（TYR，OCA2，TYRP 1和MATP）。诊断是基于皮肤和毛发色素减退的临床表现，以及特征性的眼部症状。由于OCA形式之间的临床重叠，分子诊断是必要的，以建立基因缺陷和OCA亚型。TYR和OCA 2的分子遗传学检测可在临床基础上使用，而TYRP 1和MATP的分析目前仅在研究基础上进行。鉴别诊断包括眼白化病、Hermansky-Pudlak综合征、Chediak-Higashi综合征、Griscelli综合征和Waardenburg综合征II型。携带者检测和产前诊断是可能的，当致病突变已确定在家庭中。眼镜（可能是双光眼镜）和墨镜或光致变色镜片可能对减少视觉活动和恐惧症有足够的帮助。矫正斜视和眼球震颤是必要的，建议使用防晒霜。应定期进行皮肤检查，以早期发现皮肤癌。OCA患者的寿命、发育、智力和生育能力正常。
Oculocutaneous albinism (OCA) is a group of inherited disorders of melanin biosynthesis characterized by a generalized reduction in pigmentation of hair, skin and eyes. The prevalence of all forms of albinism varies considerably worldwide and has been estimated at approximately 1/17,000, suggesting that about 1 in 70 people carry a gene for OCA. The clinical spectrum of OCA ranges, with OCA1A being the most severe type with a complete lack of melanin production throughout life, while the milder forms OCA1B, OCA2, OCA3 and OCA4 show some pigment accumulation over time. Clinical manifestations include various degrees of congenital nystagmus, iris hypopigmentation and translucency, reduced pigmentation of the retinal pigment epithelium, foveal hypoplasia, reduced visual acuity usually (20/60 to 20/400) and refractive errors, color vision impairment and prominent photophobia. Misrouting of the optic nerves is a characteristic finding, resulting in strabismus and reduced stereoscopic vision. The degree of skin and hair hypopigmentation varies with the type of OCA. The incidence of skin cancer may be increased. All four types of OCA are inherited as autosomal recessive disorders. At least four genes are responsible for the different types of the disease (TYR, OCA2, TYRP1 and MATP). Diagnosis is based on clinical findings of hypopigmentation of the skin and hair, in addition to the characteristic ocular symptoms. Due to the clinical overlap between the OCA forms, molecular diagnosis is necessary to establish the gene defect and OCA subtype. Molecular genetic testing of TYR and OCA2 is available on a clinical basis, while, at present, analysis of TYRP1 and MATP is on research basis only. Differential diagnosis includes ocular albinism, Hermansky-Pudlak syndrome, Chediak-Higashi syndrome, Griscelli syndrome, and Waardenburg syndrome type II. Carrier detection and prenatal diagnosis are possible when the disease causing mutations have been identified in the family. Glasses (possibly bifocals) and dark glasses or photocromic lenses may offer sufficient help for reduced visual activity and photophobia. Correction of strabismus and nystagmus is necessary and sunscreens are recommended. Regular skin checks for early detection of skin cancer should be offered. Persons with OCA have normal lifespan, development, intelligence and fertility.