Table 3. Mutational signatures of wild-type and mismatch repair defective cells with and without exposure to alkylating agents.

Mutation	Species	Reporter sequence	Tissue	Inducing agent	Percent C:G>T:A (%)	Percent C:G>T:A at CpG (%)	Percent C:G>T:A at CpC (%)	Percent T:A>C:G (%)	Percent C:G>A:T (%)	Percent ins/del (%)	Reference
Msh6−/−	Mouse	lacI	Small intestine	Spontaneous	73	58	—	11	5	9	(15)
Wild type	Mouse	lacI	Small intestine, thymus	Spontaneous	50	80	0	13	—	9	(16)
Wild type	Mouse	lacI	Small intestine, thymus	N -methyl-Nnitrosourea	74	7	59	0	—	8	(16)
Msh2−/−	Mouse	lacI	Small intestine, thymus	Spontaneous	42	60	20	25	—	17	(16)
Msh2−/−	Mouse	lacI	Small intestine, thymus	N-methyl-Nnitrosourea	82	15	65	0	—	16	(16)
hMSH6 3510del5 868delC	Human	HPRT	HCT15 colorectal cancer cell line	Spontaneous	25	41	19	6	46	5	(17)
hMSH6 D1145V V1192I	Human	HPRT	MT1 cells	Spontaneous	0	0	0	60	20	20	(18)
hMSH6 D1145V V1192I	Human	HPRT	MT1 cells	N′-Methyl-N ’-nitro-N -nitrosoguanidine	94	0	43	0	1	0	(18)
hMSH6 Het C1453T, Q485X; Het G3907A, A1303T	Human	500 kb (exons of protein kinases)	PD1487a	Temozolomide	100	0	47	0	0	0	This study
hMSH6 Hom delG2425, V809X	Human	500 kb (exons of protein kinases)	PD1489a	Temozolomide and BCNU	97	7	55	0	3	0	This study

NOTE: The 5′ (underlined) cytosine in the CpC dinucleotide is the one mutated.

Abbreviations: HPRT, hypoxanthine phosphoribosyltransferase; BCNU, 1,3-bis(2-chloroethyl)-1-nitrosourea.