Classification tree for detection of single-nucleotide polymorphism (SNP)-by-SNP interactions related to heart disease: Framingham Heart Study

Table 3 Prevalence of CHD in each of 17 classes identified by GUIDE^a

Class No. (Terminal No.)	No. subjects	No. CHD (%)	p-value^b
16	433	1 (0.23%)	Reference
288	489	6 (1.2%)	0.12
136	367	6 (1.6%)	<0.0001
48	335	7 (2.1%)	0.04
289	106	10 (9%)	0.0004
137	56	8 (14%)	<0.0001
5	235	36 (15%)	<0.0001
49	50	8 (16%)	<0.0001
37	73	13 (18%)	<0.0001
25	42	8 (19%)	<0.0001
145	37	7 (19%)	<0.0001
7	297	58 (20%)	<0.0001
35	43	9 (21%)	<0.0001
13	65	14 (22%)	<0.0001
69	30	7 (23%)	<0.0001
73	38	9 (24%)	<0.0001
19	56	15 (27%)	<0.0001
Overall	2752	222 (8%)	---

^aNote: GEE model deleted 160 subjects with missing SNPs, while GUIDE kept all the missing values and treated them as zero.
^bp-value from the GEE model for each class compared to the reference class (16).

ISSN: 1753-6561