Dyskeratosis congenita (DC) is an inherited bone marrow failure syndrome exhibiting considerable clinical and genetic heterogeneity. X-linked recessive, autosomal dominant and autosomal recessive forms are recognised. The gene mutated in X-linked DC (DKC1) encodes a highly conserved nucleolar protein called dyskerin. Dyskerin associates with the H/ACA class of small nucleolar RNAs which are important in guiding the conversion of uracil to pseudouracil in ribosomal RNA. Dyskerin also associates with the RNA component of telomerase (hTR) which is important in the maintenance of telomeres. Mutations in hTR were recently demonstrated in patients with autosomal dominant DC and in a subset of patients with aplastic anaemia (AA) but without other diagnostic features of DC. This discovery demonstrates that both DC and a subset of AA are due to a defect in telomerase. The link between DC and AA and in turn to defective telomerase suggests that treatments directed at correction of telomerase activity might benefit DC/AA patients who do not respond to conventional therapy.

中文翻译：

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先天性角化病：其与端粒酶和再生障碍性贫血的联系。

先天性角化病（DC）是一种遗传性骨髓衰竭综合征，表现出相当大的临床和遗传异质性。认识到X连锁隐性，常染色体显性和常染色体隐性形式。X-连锁DC（DKC1）中突变的基因编码一种高度保守的核仁蛋白，称为dyskerin。Dyskerin与小核仁RNA的H / ACA类相关，这对指导核糖体RNA中尿嘧啶向伪尿嘧啶的转化很重要。Dyskerin还与端粒酶（hTR）的RNA成分相关，端粒酶在端粒的维持中很重要。最近在常染色体显性DC患者和部分再生障碍性贫血（AA）但无DC其他诊断特征的患者中证实了hTR突变。该发现证明DC和AA的子集均归因于端粒酶的缺陷。DC与AA之间的联系，进而与端粒酶缺陷有关，表明针对端粒酶活性校正的治疗可能会使对常规疗法无反应的DC / AA患者受益。