Biegel J A, Wentz E
Division of Human Genetics and Molecular Biology, Children's Hospital of Philadelphia, Pennsylvania, USA.
Genes Chromosomes Cancer. 1997 Feb;18(2):143-6.
We have shown that an i(17q) is the most frequent abnormality in central nervous system primitive neuroectodermal tumors (PNETs; medulloblastoma), implicating the presence of a tumor suppressor gene which maps to 17p. In the present study, we investigated whether the deletion of chromosome arm 17p that results from the formation of the i(17q) is preferentially of maternal or paternal origin. Eight cases of primary PNETs of the posterior fossa were examined at five polymorphic loci which map to 17p13. Two or three informative loci were detected in each family. Of the eight cases, four tumors evidenced loss of the paternal allele for loci on 17p13 and four tumors demonstrated maternal deletions. Although the number of cases is relatively small, these studies do not implicate the loss of an imprinted gene as a mechanism for tumorigenesis in children with central nervous system PNETs/medulloblastoma.
我们已经表明，i(17q)是中枢神经系统原始神经外胚层肿瘤（PNETs；髓母细胞瘤）中最常见的异常情况，这意味着存在一个定位于17p的肿瘤抑制基因。在本研究中，我们调查了由i(17q)形成导致的17p染色体臂缺失是否优先来自母方或父方。对8例后颅窝原发性PNETs在定位于17p13的5个多态位点进行了检测。每个家系检测到2个或3个信息位点。在这8例病例中，4例肿瘤显示17p13位点的父本等位基因缺失，4例肿瘤显示母本缺失。尽管病例数量相对较少，但这些研究并未表明印迹基因的缺失是中枢神经系统PNETs/髓母细胞瘤患儿肿瘤发生的机制。
