Burt R W, Bishop D T, Cannon L A, Dowdle M A, Lee R G, Skolnick M H
N Engl J Med. 1985 Jun 13;312(24):1540-4. doi: 10.1056/NEJM198506133122403.
Except in the rare polyposis syndromes, the contribution of heritable factors to the genesis of colorectal cancer and adenomatous polyps is not well understood. We examined the inheritance of susceptibility to colonic polyps and cancer in a large Utah pedigree with multiple cases of common colorectal cancer but no recognizable inheritance pattern among them. Inheritance was clarified, however, by systematic screening for colonic polyps in pedigree members and spouse controls, using flexible proctosigmoidoscopy. One or more adenomatous polyps were found in 21 per cent of family members (41 of 191) but in only 9 per cent of controls (12 of 132) (P less than 0.005). Pedigree analysis was performed with likelihood methods that compared random occurrence of cancer and polyps with autosomal recessive and autosomal dominant patterns of inheritance. The analysis suggested that the observed excess of discrete adenomatous polyps and colorectal cancers was the result of an inherited autosomal dominant gene for susceptibility, rather than an inherited recessive gene for susceptibility or a chance occurrence. This type of inheritance of colorectal polyps and cancer may be more common than previously recognized.
除了在罕见的息肉病综合征中，遗传因素对结直肠癌和腺瘤性息肉发生的作用尚未完全明确。我们在犹他州的一个大家系中研究了结肠息肉和癌症易感性的遗传情况，该家系中有多例常见的结直肠癌，但在这些病例中未发现明显的遗传模式。然而，通过使用可弯曲乙状结肠镜对家系成员和配偶对照进行结肠息肉的系统筛查，遗传情况得以明确。在21%的家庭成员（191人中的41人）中发现了一个或多个腺瘤性息肉，而在对照中仅为9%（132人中的12人）（P小于0.005）。采用似然法进行系谱分析，将癌症和息肉的随机发生情况与常染色体隐性和常染色体显性遗传模式进行比较。分析表明，观察到的离散腺瘤性息肉和结直肠癌的过多现象是由一个遗传性常染色体显性易感性基因导致的，而非遗传性隐性易感性基因或偶然发生。这种类型的结肠息肉和癌症遗传可能比之前认为的更为常见。
