El cáncer oral en México, se ubica el lugar 21 incidencia y 24 mortalidad, sin embargo, cada década su aumenta debido a la exposición factores de riesgo que han sido asociados esta neoplasia: consumo tabaco alcohol, exposiciones virales eventos genéticos específicos dentro los destacan presencia variante c.-93G>A metilación del gen MLH1, por lo objetivo presente revisión centra describir imp...

Introduction: Annual effective radiation dose from all natural sources is approximately about 2.4 mSv and contribution of unnatural or man-made sources is 0.8 mSv. In some places of Ramsar, radiation dose due to radon exposure is about 3700 Bqm -3 while according to US EPA instruction radon levels should be 200 Bq m-3. Amazingly, there is not a meaningful result in the studies...

To test whether missense mutations in the cancer susceptibility gene MLH1 adversely affect meiosis, we examined 14 yeast MLH1 mutations for effects on meiotic DNA transactions and gamete viability in the yeast Saccharomyces cerevisiae. Mutations analogous to those associated with hereditary nonpolyposis colorectal cancer (HNPCC) or those that reduce Mlh1p interactions with ATP or DNA all impair...

MutL homologs belong to a family of proteins that share a conserved ATP binding site. We demonstrate that amino-terminal domains of the yeast MutL homologs Mlh1 and Pms1 required for DNA mismatch repair both possess independent, intrinsic ATPase activities. Amino acid substitutions in the conserved ATP binding sites concomitantly reduce ATP binding, ATP hydrolysis, and DNA mismatch repair in vi...

Meiotic chromosome pairing involves not only recognition of homology but also juxtaposition of entire chromosomes in a topologically regular way. Analysis of filamentous fungus Sordaria macrospora reveals that recombination proteins Mer3, Msh4, and Mlh1 play direct roles in all of these aspects, in advance of their known roles in recombination. Absence of Mer3 helicase results in interwoven chr...

Synthetic sickness/lethality (SSL) can be exploited to develop therapeutic strategies for cancer. Deficiencies in the tumor suppressor proteins MLH1 and MSH2 have been implicated in cancer. Here we demonstrate that deficiency in MSH2 is SSL with inhibition of the DNA polymerase POLB, whereas deficiency in MLH1 is SSL with DNA polymerase POLG inhibition. Both SSLs led to the accumulation of 8-ox...

Germ line mutations in DNA mismatch repair genes including MLH1 cause hereditary nonpolyposis colon cancer. To understand the role of MLH1 in normal growth and development, we generated mice that have a null mutation of this gene. Mice homozygous for this mutation show a replication error phenotype, and extracts of these cells are deficient in mismatch repair activity. Homozygous mutant males s...

BACKGROUND Genetic instability is a characteristic feature of familial and sporadic breast carcinomas. It is not clear whether defects in the mismatch repair system accompany this instability. The purpose of this study was to explore the expression of two of the proteins encoded by the DNA mismatch repair genes, namely MLH1 and MSH2, in sporadic in situ and invasive breast carcinomas of various...