Mutation screening of mismatch repair gene Mlh3 in familial esophageal cancer

Table 1 Esophageal cancer family

Type	Family
TCR1	1, 5, 8, 10
MCR2	2, 3 ,4, 6, 7, 9

TCR¹: Two first-degree relatives with esophageal cancer; MCR²: Three or more relatives with esophageal cancer.

Table 2 Sequence, length and annealing temperature for primers

Primer sequence	Length	Annealing temperature
	(bp)	(°C)
MLH3 F1-1: TCC AGT CAG AGA AGG AAA CCA	524	Touch down
MLH3 R1-1: ACA GGA AGC TGG TAA AAT AG		58-51
MLH3 F1-2: CTG ATG TGA CTA GAG CAA GCG	552	Touch down
MLH3 R1-2: CAT CAT ACT CAC AGA ATT GGC AC		58-51
MLH3 F1-3: ATT CAA GTC TTC GGC ACC	512	Touch down
MLH3 R1-3: TTT GTT TTG TAA AGA TGG CTC TG		58-51
MLH3 F1-4: GGG ATT CAG AAG CTA CCA	602	Touch down
MLH3 R1-4: TGA ATG TTC TGT TTC AGT TGA TTT		58-51
MLH3 F1-5: GGG CGA GTT AAA TTA TGT TCC A	562	Touch down
MLH3 R1-5: CTT GAA GAC TGA GAT TGG TAG TGA		58-51
MLH3 F1-6: TGG GAA GGT TGA AAA TCC TC	557	Touch down
MLH3 R1-6:AGG AAT TAT CCT GTG TGG CAG		58-51
MLH3 F1-7: CAG AGA ATG GTG TCA TCC CAA	551	Touch down
MLH3 R1-7: CCT TGT CCA GCA TTC CCA T		58-51
MLH3 F2: TGT CTT GAC TCA GTT TGT GCA G	247	62
MLH3 R2: ACG ATG TGT ACT GTG TGC CC
MLH3 F3: TGG TTC TGG ATG CCA ACT TT	229	59
MLH3 R3: ATT TCA GTC TGG GCA ACA GG
MLH3 F4: CAA TTA TAT TTT GCT GAG TC	158	52
MLH3 R4: ATG AGA TTT TGA AGT TAA TC
MLH3 F5: CCC AGT CTC AAA GAA AGG AGT	239	57
MLH3 R5: AGC TGG TTA GTC ATT CAG GC
MLH3 F6: CAT GAT GGT TGT CGT CTT GC	185	60
MLH3 R6: GGT GTA CTG ATT CTG CTG GGA
MLH3 F7: TTC CCT TCC TAC TCT TAA CCC A	265	59
MLH3 R7: TGT AAC CTC TCT TGG TCT CAT CTG
MLH3 F8: TTT GGA ACC AGT AGT GAA GTG C	267	57
MLH3 R8: CAG CAA TTT CCT TAA CAT CTG C
MLH3 F9/10: CGT AGA TTA AAG CCG ATT TTC		329 59
MLH3 R9/10:TGT ACC CTC TGC CTC TTT CG
MLH3 F11: GTC AGC ATT GGT TTC CCA CT	251	59
MLH3 R11: AAA CTT TGC TCC CTC CTG CT
MLH3 F12: GCC CAG CCT GTA TGC TAC CT	226	59
MLH3 R12: CAG TGA CAC TCC CTT TGT TCC

Table 3 Possible mutations of Mlh3 in familial esophageal cancer

Exon	Nucleotide	Amino	Family	Family	Cosegregation	Frequency in	Frequency in sporadic	Frequency in normal
	change1	change		type		FEC n (%)	EC n (%)	control n (%)
1	A2173C	Asn725His	9	MCR	Yes	4/66 (6.1)	0/94 (0)	0/96 (0)
1	C2825T	Thr9421Ile	10	TCR	Yes	3/66 (4.5)	1/95 (1.0)	0/96 (0)
7	T3826C	Trp1276Arg	1	TCR	No	3/66 (4.5)	0/96 (0)	0/96 (0)
12	G4335A	Gln1445Glu	7	MCR	No	6/66 (9.1)	0/95 (0)	0/96 (0)

¹ Numbering is according to the cDNA starting at the A in the start codon, Genbank AF195657.

Table 4 Polymorphism of Mlh3

Exon	Nucleotide change1	Amino change	Family
1	C2531T	Pro8441Leu	Many
1	C2838A	Ser947Ser	Many
9/10	IVS9 + 66A→G	Unknown	Many

¹Numbering is according to the cDNA starting at the A in the start codon Genbank AF195657.