中文摘要：

内源性逆转录病毒（endogenous retrovirus，ERV）是在生物进化过程中外源性逆转录病毒感染宿主生殖细胞，继而整合入基因组而被后代遗传下来的产物。虽然之前被认为是垃圾DNA序列，但越来越多的研究表明，ERV不但有着重要的生理功能，如参与胎盘的形态发生和抑制外源性逆转录病毒的感染等，还可能与某些疾病，如肿瘤的发生相关。主要围绕人和小鼠中的内源性逆转录病毒，就其生物学功能以及与肿瘤的关系作一简要综述。

英文摘要：

Endogenous retrovirus （ERV） sequences represent relics of ancestral exogenous retrovirus infection of germ-line cells during evolution. ERVs were once thought to be junk DNA sequences. However, a growing number of studies have shown that ERVs play important physiological roles, including mammalian placental development and suppression of infection of exogenous retrovirus. In addition, ERVs have been implicated in certain diseases such as cancer. This review, focusing on the human and mouse ERVs, summarized the biological functions of ERVs as well as its relationship with cancer.