Barlow D P
The Netherlands Cancer Institute (H5), Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands.
EMBO J. 1997 Dec 1;16(23):6899-905. doi: 10.1093/emboj/16.23.6899.
Imprinted genes, in contrast to the majority of mammalian genes, are able to restrict expression to one of the two parental alleles in somatic diploid cells. Although the silent allele of an imprinted gene appears to be transcriptionally repressed, it often bears little other resemblance to normal genes in an inactive state. The key to the imprinting mechanism may be a form of parental-specific expression-competition between cis-linked genes and not parental-specific expression versus repression. Thus, the imprinting mechanism may be better understood if the chromosomal region containing imprinted genes is viewed as 'active' on both parental chromosomes.
与大多数哺乳动物基因不同，印记基因能够在体细胞二倍体细胞中将表达限制在两个亲本等位基因中的一个。尽管印记基因的沉默等位基因似乎在转录上受到抑制，但它在非活性状态下与正常基因几乎没有其他相似之处。印记机制的关键可能是顺式连锁基因之间一种亲本特异性的表达竞争形式，而不是亲本特异性表达与抑制的关系。因此，如果将包含印记基因的染色体区域视为在两条亲本染色体上都是“活跃的”，那么印记机制可能会得到更好的理解。
