Fig. 1

Tetra-ARMS PCR electrophoretic pattern of the EGFR (rs121913438) product, where each lane represents one participant. M stands for DNA marker (100 bp). The internal control is shown by the 444 bp band. Based on the primer, specific 325 bp bands represent the mutant (D) allele, and specific 134 bp bands represent the wild (W) allele. WD heterozygous is represented by lanes 1, 2, 3, and 5. Lane 4 indicates mutant homozygous, where the W allele is absent from the lane and the D allele is present at 325 bp. Lane 6 represents wild-type homozygosity, with the W allele appearing at 134 bp and the D allele absent