Distribution and haplotype associations of XPD Lys751Gln, XRCC1 Arg280His and XRCC1 Arg399Gln polymorphisms with nasopharyngeal carcinoma in the Malaysian population.
BACKGROUND
DNA repair pathways play a crucial role in maintaining the human genome. Previous studies associated DNA repair gene polymorphisms (XPD Lys751Gln, XRCC1 Arg280His and XRCC1 Arg399Gln) with nasopharyngeal carcinoma. These non-synonymous polymorphisms may alter DNA repair capacity and thus increase or decrease susceptibility. The present study aimed to determine the genotype distribution of XPD codon 751, XRCC1 codon 280 and codon 399 polymorphisms and haplotype associations among NPC cases and controls in the Malaysian population.


METHODS
We selected 157 NPC cases and 136 controls from two hospitals in Kuala Lumpur, Malaysia for this study. The polymorphisms studied were genotyped by PCR-RFLP assay and allele and genotype frequencies, haplotype and linkage disequilibrium were determined using SNPstat software.


RESULTS
For the XPD Lys751Gln polymorphism, the frequency of the Lys allele was higher in cases than in controls (94.5% versus 85.0%). For the XRCC1 Arg280His polymorphism, the frequency of Arg allele was 90.0% and 89.0% in cases and controls, respectively and for XRCC1 Arg399Gln the frequency of the Arg allele was 72.0% and 72.8% in cases and controls respectively. All three polymorphisms were in linkage disequilibrium. The odds ratio from haplotype analysis for these three polymorphisms and their association with NPC was 1.93 (95%CI: 0.90-4.16) for haplotype CGC vs AGC allele combinations. The global haplotype association with NPC gave a p-value of 0.054.


CONCLUSIONS
Our study provides an estimate of allele and genotype frequencies of XRCC1Arg280His, XRCC1 Arg399Gln and XPD Lys751Gln polymorphisms in the Malaysian population and showed no association with nasopharyngeal cancer.
Department of Community Health Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Malaysia E-mail : lyems9@yahoo.com.
Shaneeta
S
Visuvanathan
Pei-Pei
PP
Chong
Yoke-Yeow
YY
Yap
Chin-Chye
CC
Lim
Meng-Kuan
MK
Tan
Munn-Sann
MS
Lye
D002277:Carcinoma; D016022:Case-Control Studies; D004260:DNA Repair; D004268:DNA-Binding Proteins / Q000235:genetics*; D005838:Genotype; D006239:Haplotypes / Q000235:genetics*; D006801:Humans; D015994:Incidence; D008296:Malaysia / Q000453:epidemiology; D000077274:Nasopharyngeal Carcinoma; D009303:Nasopharyngeal Neoplasms / Q000453:epidemiology / Q000235:genetics*; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic / Q000235:genetics*; D012150:Polymorphism, Restriction Fragment Length; D012307:Risk Factors; D000076105:X-ray Repair Cross Complementing Protein 1; D051759:Xeroderma Pigmentosum Group D Protein / Q000235:genetics*
D004268:DNA-Binding Proteins; D000076105:X-ray Repair Cross Complementing Protein 1; C000619371:XRCC1 protein, human; D051759:Xeroderma Pigmentosum Group D Protein; C497292:ERCC2 protein, human