[Germ-line epimutations and human cancer].
Epimutations are errors in the normal process of epigenetic regulation which can result in aberrant transcriptional silencing of a normally active gene or reactivation of a normally silent gene. Epimutations are generally considered to be somatic events and to be confined in affected tissues. However, recent studies of patients with hereditary nonpolyposis colorectal cancer (HNPCC) have showed that allele-specific hypermethylation of CpG islands in the promoter region of the MLH1 gene, one of the causes of the tumor, existed in all the tissues examined. In addition, germ-line epimutations of other tumor suppressor genes (TSGs), such as MSH2 and BRCA1, have also been reported, demonstrating that epimutations might arise in the germ-line (during gametogenesis or early embryonic development). The role of germ-line epimutations might be as important as germ-line mutations in human disease. We reviewed the update on germ-line epimutations of TSGs including the possible mechanisms underlying germ-line epimutations, the possibility of transgenerational inheritance, and their impact on our understanding of human disease.
Wu
Pu-Yuan
PY
Department of Medical Genetics,Medical School, Nanjing University,Nanjing, Jiangsu 210093, P. R. China.
Fan
Yi-Mei
YM
Wang
Ya-Ping
YP
D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics* / Q000378:metabolism; D000818:Animals; D019313:BRCA1 Protein / Q000235:genetics; D003123:Colorectal Neoplasms, Hereditary Nonpolyposis / Q000235:genetics*; D018899:CpG Islands; D019175:DNA Methylation; D044127:Epigenesis, Genetic; D018095:Germ-Line Mutation; D006801:Humans; D019656:Loss of Heterozygosity; D053842:Microsatellite Instability; D000070957:MutL Protein Homolog 1; D051718:MutS Homolog 2 Protein / Q000235:genetics; D009687:Nuclear Proteins / Q000235:genetics* / Q000378:metabolism; D011401:Promoter Regions, Genetic
D048868:Adaptor Proteins, Signal Transducing; D019313:BRCA1 Protein; C501486:MLH1 protein, human; D009687:Nuclear Proteins; C497172:MSH2 protein, human; D000070957:MutL Protein Homolog 1; D051718:MutS Homolog 2 Protein