Table 2.

Association between age at diagnosis and number of risk alleles at known glioma risk loci in combined UCSF Adult Glioma Study and Mayo Clinic patients, stratified by tumor cell type

SNP	Chromosome	Gene	Risk Allele	All Gliomas		Purely Astrocytic Tumorsa		Tumors With an Oligo Componentb		Heterogeneity Testsc
				Effect (SE)d	Pe	Effect (SE)d	Pe	Effect (SE)d	Pe	P	I2
Rs2736100	5	TERT	C	1.47 (0.43)	6.2 × 10−4	1.38 (0.48)	4.3 × 10−3	0.85 (0.74)	0.25	0.55	0
Rs11979158	7	EGFR	A	0.48 (0.60)	0.43	0.78 (0.68)	0.25	−1.37 (1.05)	0.19	0.086	66.16
Rs55705857	8	CCDC26	G	-	-	−7.25 (0.93)	1.2 × 10−14	−2.81 (0.94)	3.1 × 10−3	8.0 × 10−4	91.15
Rs1412829	9	CDKN2B/ANRIL	G	-	-	0.55 (0.47)	0.24	−1.91 (0.77)	0.013	6.2 × 10−3	86.66
Rs498872	11	PHLDB1	A	-	-	−2.30 (0.48)	2.1 × 10−6	0.25 (0.73)	0.73	3.5 × 10−3	88.31
Rs78378222	17	TP53	C	-	-	−2.49 (1.35)	0.065	4.25 (2.45)	0.084	0.016	82.77
Rs6010620	20	RTEL1	G	2.02 (0.55)	2.5 × 10−4	1.80 (0.63)	4.3 × 10−3	0.81 (0.91)	0.37	0.37	0

^aIncludes glioblastomas (n = 1217), and grades II–III astrocytomas (n = 555).

^bIncludes oligodendrogliomas (n = 277) and mixed oligoastrocytomas (n = 230).

^cP-values from Cochran’s Q-statistic, testing for heterogeneity in beta across strata of tumor cell type (purely astrocytic vs oligodendroglial). I² can range from 0 to 100, where larger numbers indicate a greater level of heterogeneity across histology strata.

^dEffect size (in y) is generated from a linear regression model where age at diagnosis is the dependent variable and number of risk alleles is the independent variable, controlling for sex and study site. Positive values indicate older age at diagnosis with an increasing number of risk alleles. Negative values indicate younger age at diagnosis with an increasing number of risk alleles.

^eP-values are 2-sided and are derived from the regression model (H₀: beta = 0). A total of 11 statistical comparisons are considered (1 comparison per SNP for the 3 loci displaying no heterogeneity of effect across tumor types; 2 comparisons per SNP for the 4 loci displaying significant heterogeneity of effect across tumor types). A strict Bonferroni correction for these 11 comparisons corresponds to an adjusted significance threshold of 4.5 × 10⁻³ (0.05/11). P-values in bold were considered statistically significant.