Table 1.

Sequences of primers used to amplify and sequence EGFR exons 18 to 21

Exon	Sequence 5'→3'	Tm (°C)
18	for CAAATGAGCTGGCAAGTGCCGTGTC rev GAGTTTCCCAAACACTCAGTGAAAC	58
19	for GCAATATCAGCCTTAGGTGCGGCTC rev CATAGAAAGTGAACATTTAGGATGTG	67
20	for CCATGAGTACGTATTTTGAAACTC rev CATATCCCCATGGCAAACTCTTGC	58
21	for CTAACGTTCGCCAGCCATAAGTCC rev GCTGCGAGCTCACCCAGAATGTCTGG	67

The annealing temperature is shown. For and rev are primers forward and reverse respectively according to the gene transcription orientation. Forward primers were used to sequence all PCR products and reverse primers to confirm the presence of mutation.