Pigmentary disorders with anomalies of skin, hair and iris pigmentation are frequently found associated with congenital hearing impairment in several syndromes like Waardenburg syndrome (WS) or Tietz Albinism‐Deafness syndrome (TADS; OMIM: 103500). WS can be subclassified in four major WS types and differential diagnosis is based on additional clinical features. Dystopia canthorum or telecanthus is characteristic for WS1 (OMIM: 193500) and WS3 (OMIM: 148820). WS2 is genetically heterogeneous and subcategorized in at least five types, WS2A to WS2E (OMIM: 193510; 600193; 606662; 608890; 611584). WS2 is characterized by absence of lateral displacement of the inner eye canthi and other midface defects as seen in WS1.

中文翻译：

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纯合内含子MITF突变导致2A型严重Waardenburg综合征

在一些综合征中，如Waardenburg综合征（WS）或Tietz白化病-耳聋综合征（TADS; OMIM：103500），经常发现与皮肤，头发和虹膜色素沉着异常有关的色素性疾病与先天性听力障碍有关。WS可以分为四种主要WS类型，而鉴别诊断基于其他临床特征。WS1（OMIM：193500）和WS3（OMIM：148820）的特征是，反乌托邦或圆锥角形。WS2在遗传上是异质的，并且至少分为WS2A至WS2E五类（OMIM：193510； 600193； 606662； 608890； 611584）。WS2的特点是没有内眼Canthi的横向移位和其他中面缺陷，如WS1所示。