Öz
Colorectal cancer (CRC) comprises
approximately 10% of all cancers and is a major cause of cancer-related
morbidity and mortality despite current diagnostic and treatment improvements.
DNA damage and altered DNA replication through the deregulation of related
genes cause genomic instability in sporadic CRC. DNA repair is very complex;
many factors play a role to ensure that the restoration of errors occurs during
the transfer of genetic material. MutL homolog 1 (MLH1) is one of the vital DNA
repair genes responsible for genomic stability. Together with environmental
factors, the genetic background may be associated with CRC development; thus,
genetic polymorphisms are considered as risk factors. The present prospective
case–control study aimed to determine the association between 93G>A and
I219V polymorphisms of MLH1 and CRC susceptibility in a Turkish population. The
genotyping of 158 patients and 164 age- and sex-matched controls was performed
by polymerase chain reaction-restriction fragment length polymorphism. Two
variants, 93G>A and I219V, were associated with an increased risk of CRC.
Individuals with A allele of 93G>A had an approximately 2-fold risk (OR:
1.92, 95% CI: 1.22–3.04; p<0.01) and those with G allele of I219V had an
approximately 3-fold risk (OR: 2.82, 95% CI: 1.76–4.52; p<0.01) of
developing CRC. Our results provide novel information for understanding the
influence of MLH1 on CRC risk in the Turkish population; however, further
studies with a larger number of participants are required.
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