基因组印记与基因组印记病

基因组印记(又称遗传印记)是指基因根据亲代的不同而有不同的表达。印记基因的存在能导致细胞中两个等位基因的一个表达而另一个不表达。基因组印记是一正常过程，此现象在一些低等动物和植物中已发现多年。印记的基因只占人类基因组中的少数，可能不超过5%，但在胎儿的生长和行为发育中起着至关重要的作用。基因组印记病主要表现为过度生长、生长迟缓、智力障碍、行为异常。目前在肿瘤的研究中认为印记缺失是引起肿瘤最常见的遗传学因素之一。本文就基因组印记及基因组印记病进行综述。

Genomic imprinting and genomic imprinting disorder

Genomic imprinting (genetic imprinting) refers to parent of origin dependent gene expression. The presence of imprinted gene can cause cells with a full parental complement of functional autosomal genes to specifically express one allele but not the other, resulting in monoallelic expression of imprinted loci. Genomic imprinting is a normal process and has been found in primary animals and plants for a long time. Imprinted genes play a critical role in fetal growth and behavioral development even though they account for less than 5% of all human genes. Abnormal imprinting effects are associated with clinical disorders of overgrowth, undergrowth, mental retardation, or behavior abnormalities. In particular, loss of imprinting (LOI) is one of the most frequent genetic alterations in cancer. This review focused on genomic imprinting and disorders of genomic imprinting.