Clinicopathological and molecular genetic analysis of 4 typical Chinese HNPCC families

Table 1 Clinicopathological charcateristics, MSI status, immunostaining and the affected MMR genes

Family	Onsetage	Number of CRC	Tumor site	MSI status	Immunostaining		Gene
					hMSH2	hMLH1
H2	29	4	Right Colon χ²; rectum χ²	4/5	-	+	hMSH2
H9	67	2	Hepatic flexure; transverse colon	4/5; 5/5	+	-	hMLH1
H11	58	2	Rectum χ²	4/5	-	+	hMSH2?
H27	38	2	Cecum; transversecolon	3/5	-	+	hMSH2

Table 2 Pathological germ-line mutations in the hMLH1 and hMSH 2 genes

Family	Gene	Exon	Codon	Mutation	Nucleotide Change
H2	hMSH2	13	680	Nonsense	CGA-TGA (stop codon)
H9	hMLH1	11	305	In-frame deletion	24 bp deletion
H27	hMSH2	3	206	Frame shift	1 bp (A) insertion; stop at 73 bp downstream of the mutation