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for nasopharyngeal cancer, patients with the XRCC1
G28152A codon 399 Arg/Gln polymorphism experi-
enced a significantly lower grade of fibrosis than
patients with the wild-type allele. The XRCC3 C18067T
codon 241 Thr/Met SNP was not associated with extent
of fibrotic response post radiotherapy in this group of
patients. 256
Considering this early evidence, future clinical trials
of radiotherapy-based treatments should routinely
incorporate a collection of genomic DNA to facilitate
the compilation of pharmacogenomic data and further
establish the significance of DNA repair gene SNPs on
clinical response to radiotherapy.
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we have provided a comprehensive summary of
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