Chu G, Mayne L
Department of Medicine, Stanford University Medical Center, CA 94305, USA.
Trends Genet. 1996 May;12(5):187-92. doi: 10.1016/0168-9525(96)10021-4.
Xeroderma pigmentosum, Cockayne syndrome and trichothiodystrophy are three distinct human syndromes associated with sensitivity to ultraviolet radiation. We review evidence that these syndromes overlap with each other and arise from mutations in genes involved in nucleotide-excision repair and RNA transcription. Attempts have been made to explain the syndromes in terms of defects in repair and transcription. These two biochemical pathways do not easily account for all the features of the syndromes. Therefore, we propose a third pathway, in which the syndromes are due, in part, to defects in a demethylation mechanism involving the excision of methylated cytosine. Perturbation of demethylation could affect the developmentally regulated expression of some genes.
着色性干皮病、科凯恩综合征和毛发硫营养不良是三种与紫外线辐射敏感性相关的不同人类综合征。我们回顾了相关证据，这些综合征相互重叠，且由参与核苷酸切除修复和RNA转录的基因突变引起。人们曾试图从修复和转录缺陷的角度来解释这些综合征。然而，这两条生化途径难以解释这些综合征的所有特征。因此，我们提出了第三条途径，即这些综合征部分归因于涉及甲基化胞嘧啶切除的去甲基化机制缺陷。去甲基化的扰动可能会影响某些基因在发育过程中的调控表达。
