At tetrad stage, dyad, triad, tetrad with micronucleus and polyad appeared. 四分体时期还出现二分体、三分体、含微核的异常四分体及多分体。
Dyskeratosis congenita (DKC) is a rare inherited disease characterized by the triad of abnormal skin pigmentation, nail dystrophy, and mucosal leukoplakia. 先天性角化不良症(DKC)为一少见之遗传性疾病,三项主要特徵为皮肤色素异常、 指甲生长异常及黏膜白斑症。