Table 1

Clinical features of families 1–3

ID	Age GAPPS first diagnosed (years)	Stomach (age at diagnosis of cancer)	Colorectum	Helicobacter pylori	Gastrectomy
Family 1
II-2	72	Normal	1 rectal TA	Unknown	No
II-4	77	H pylori gastritis	5 mm caecal TVA	Positive	No
II-11	68	H pylori gastritis	One rectal HP	Positive	No
II-13	58	H pylori gastritis	Unknown	Positive	No
III-1	33	GAPPS	Normal	Negative	Yes
III-5	51	GAPPS	Unknown	Negative	No
III-7	46	GAPPS	Five distal and three proximal TAs at four colonoscopies over 4 years	Negative	Yes
III-13	53	GAPPS	One rectal HP	Negative	Yes
III-15	56	GAPPS	Three rectosigmoid HPs	Negative	Yes
III-16	55	Normal	One TA, one rectal HP	Positive	No
III-17	49	GAPPS	One rectal HP	Negative	No
III-18	52	GAPPS	Unknown	Negative	No
III-21	49	Uncertain, seven FGPs	Two rectal HPs	Negative	No
III-22	37	Uncertain, 17 FGPs	Normal	Negative	No
III-23	46	Uncertain, 15 FGPs	Three proximal TAs, one proximal HP, five rectosigmoid HPs	Negative	No
III-24	44	GAPPS—gastric adenocarcinoma (48 years)	Unknown	Negative	No
III-25	50	Uncertain, 25 FGPs	One distal TA and three rectal HPs	Negative	No
III-26	37	GAPPS	Normal	Negative	Yes
III-28	46	Normal	One rectal HP	Unknown	No
III-29	41	GAPPS	One proximal HP	Negative	Yes
III-30	56	GAPPS	One proximal and one distal TA	Negative	No
III-31	55	GAPPS	Unknown	Unknown	No
IV-1	10	GAPPS	Normal	Negative	No
IV-2	14	GAPPS	Unknown	Negative	No
IV-3	32	GAPPS—gastric adenocarcinoma (33 years)	Unknown	Unknown	No
IV-4	31	GAPPS	One proximal and one distal TA	Negative	Yes
IV-5	26	Normal	Normal	Negative	No
IV-6	31	Normal	Normal	Negative	No
IV-7	26	Normal	Unknown	Negative	No
IV-8	24	GAPPS	Unknown	Negative	No
IV-11	24	GAPPS	Normal	Negative	Yes
IV-12	29	Normal	Normal	Negative	No
IV-13	35	Uncertain, 30 FGPs	Normal	Unknown	No
IV-15	25	GAPPS	Normal	Negative	No
IV-17	26	Uncertain, four FGPs	Normal	Negative	No
IV-20	20	Normal	Normal	Unknown	No
IV-21	18	GAPPS	Normal	Negative	Yes
IV-24	36	Normal	Normal	Negative	No
Family 2
II-12	75	GAPPS—gastric adenocarcinoma (75 years)	Unknown	Unknown	No
III-17	49	GAPPS—gastric adenocarcinoma (49 years)	Unknown	Unknown	No
III-18	49	Normal	Unknown	Unknown	No
III-19	34	GAPPS	Unknown	Negative	Yes
III-21	58	GAPPS	Three polyps, histology unknown	Negative	Yes
III-23	50	GAPPS—gastric adenocarcinoma (50 years)	Normal	Unknown	No
III-24	47	Normal	Unknown	Unknown	No
IV-2	22	Normal	Unknown	Negative	No
IV-3	19	Normal	Unknown	Negative	No
IV-4	24	GAPPS	Unknown	Negative	No
IV-5	23	GAPPS	Unknown	Unknown	No
IV-6	17	Normal	Unknown	Negative	No
IV-7	15	Normal	Unknown	Negative	No
Family 3
I-4	50	Likely GAPPS—gastric adenocarcinoma (50 year)	Unknown	Unknown	No
II-2	34	GAPPS—gastric adenocarcinoma (34 years)	Unknown	Unknown	No
II-3	33	GAPPS	Normal	Negative	Yes
II-4	36	GAPPS	Unknown	Unknown	No

FGP, fundic gap polyp; GAPPS, gastric adenocarcinoma and proximal polyposis of the stomach; HP, hyperplastic polyp; TA, simple tubular adenoma; that is, ≤10 mm, no high-grade dysplasia; TVA, tubulovillous adenoma.