Relationship between XPD Lys 751 Gln polymorphism and colorectal cancer risk: a case-control study in a population-based study.
OBJECTIVE
In our study, we analyzed the allelic frequency of XPD Lys751Gln polymorphism of the XPD gene and the correlation between its variant alleles with colorectal cancer in patients and control groups.


BACKGROUND
Human cells are routinely exposed to mutagenic and carcinogenic aromatic amines via smoking, pollution areas and other sources. These chemicals can form DNA adducts in vivo and thus lead to DNA damage. Amongst the known genetic polymorphisms of the DNA-repair genes the xeroderma pigmentosum group D (XPD, also known as ERCC2) has been the most extensively studied most commonly.


METHODS
This study has examined the relationship between the XPD Lys 751 Gln polymorphism and colorectal cancer in 88 patients and their 88 age and sex-matched controls. Genomic DNA from peripheral whole blood was extracted using Miller method to determine the genotype of subjects with RFLP-PCR analysis.


RESULTS
This study shows cancer patients have more of the heterozygous genotype (XPD Lys 751 Gln) compared to control group. However the results are not statistically significant. Furthermore, colorectal cancer was less common in individuals with recessive homozygous genotype (P< 0.0001).


CONCLUSIONS
This study suggests that individuals with heterozygous polymorphism (Lys/Gln) may have an increased susceptibility to colorectal cancer compared to other polymorphisms (Lys/Lys and Gln/Gln).
Genetic Division, Biology Department, School of Sciences, The University of Isfahan, Isfahan, Iran.
Hojatolah
H
Rezaei
Genetic Division, Biology Department, School of Sciences, The University of Isfahan, Isfahan, Iran.
Majid
M
Motovali-Bashi
National Research Institute of Tuberculosis and Lung Disease, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Kian
K
Khodadad
Director of Qom Blood Transfusion Center, Qom, Iran.
Ali
A
Elahi
National Research Institute of Tuberculosis and Lung Disease, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Habib
H
Emami
Genetic division, Biology Department, School of Sciences, The University of Tabriz, Tabriz, Iran.
Hossein
H
Naddaffnia
Colorectal cancer; Nucleotide excision repair; XPD gene; polymorphism