Dietary, lifestyle and clinicopathological factors associated with BRAF and K-ras mutations arising in distinct subsets of colorectal cancers in the EPIC Norfolk study

Table 1 The type and distribution of mutations in BRAF and K-ras in the 186 adenocarcinoma and 16 adenoma tissues available from EPIC Norfolk.

	BRAFmutation
	Mutations in adenocarcinomas	Mutations in adenomas	Total
Codon 600: wildtype GTG
GAG (Val to Glu)	29	0	29
Total	29	0	29
	*K-ras* mutation
	Mutations in adenocarcinomas	Mutations in adenoma	Total
Codon 12: wildtype GGT
GCT (Gly to Ala)	7	1	8
GTT (Gly to Val)	6	1	7
GAT (Gly to Asp)	14	2	16
TGT (Gly to Cys)	4	1	5
AGT (Gly to Ser)	1	0	1
Undetermined*	1	0	1
Codon 13: wildtype GGC
GAC (Gly to Asp)	6	1	7
TGC (Gly to Cys)	1	0	1
Codon 19: wildtype TTG
GTT (Leu to Phe)**	1	0	1
Codon 20: wildtype ACG
GCG (Thr to Ala)**	1	0	1
Codon 89: wildtype TCA
TTA (Ser to Stop)	0	1	1
Total	42	7	49

*: One adenocarcinoma sample was classified as mutated by both sequencing methods but the base change identified was not consistent. Dideoxysequencing identified the base change as G to A, pyrosequencing as G to C. Repeated sequencing using both methods did not resolve this and as such the base change was unclassified. **: The two mutations observed in codons 19 and 20 were in the same adenocarcinoma.

ISSN: 1471-2407