Easton D, Peto J
Institute of Cancer Research, Sutton, Surrey.
Cancer Surv. 1990;9(3):395-416.
Only a small proportion of cancers, arising in inherited syndromes such as polyposis coli, have an unequivocally inherited basis. Nevertheless, most common cancers show familial clustering, much of which may be due to inherited predisposition. If so, there may be wide variation in genetic susceptibility to common cancers. The precise models of susceptibility are unclear, but for ovarian cancer and breast cancer there is some evidence that a small proportion of cases result from highly penetrant dominant genes. This has been confirmed recently for breast cancer by genetic linkage studies. Clear evidence for genetic susceptibility has been obtained for Hodgkin's disease and nasopharyngeal carcinoma, where the existence of susceptibility genes at the HLA locus has been demonstrated by linkage analysis. These genes could account for the majority of cases of these cancers. Identification of other cancer susceptibility genes should be possible, either directly using linkage analysis, or through identification of constitutional phenotypes related to cancer risk.
只有一小部分癌症起源于诸如结肠息肉病等遗传性综合征，具有明确的遗传基础。然而，大多数常见癌症呈现家族聚集性，其中很大一部分可能归因于遗传易感性。如果是这样，那么对常见癌症的遗传易感性可能存在广泛差异。易感性的确切模式尚不清楚，但对于卵巢癌和乳腺癌，有一些证据表明一小部分病例是由高外显率的显性基因导致的。最近通过基因连锁研究已证实乳腺癌存在这种情况。对于霍奇金病和鼻咽癌，已经获得了遗传易感性的明确证据，通过连锁分析已证明HLA位点存在易感基因。这些基因可能导致这些癌症的大多数病例。通过直接使用连锁分析或通过识别与癌症风险相关的体质表型，应该有可能鉴定出其他癌症易感基因。
