Table 4.

Covariate adjustment for association of SLC26A9 SNP rs7512462 with NBS IRT in the Colorado and Wisconsin combined samples (n = 148).

Covariate in Model	pSNP	βSNP (95% CI)	pcovariate	R2 model
None (rs7512462 only)	6.77 × 10−5	−51 (−76, −26)	N/A	0.10
Sex	7.30 × 10−5	−51 (−76, −26)	0.72	0.10
CFTRa	2.02 × 10−5	−56 (−80, −31)	0.06	0.13
Age at IRT measurement (days)	1.56 × 10−4	−51 (−77, −25)	0.95	0.10
IRT assay	4.85 × 10−5	−52 (−77, −28)	0.16	0.12
Meconium ileusb	1.37 × 10−4	−48 (−72, −24)	1.90 × 10−4	0.19
Principal componentsc	2.32 × 10−5	−56 (−81, −31)	0.15	0.13
Site	9.87 × 10−5	−51 (−77, −25)	0.74	0.10

^a: Subjects are classified as delF508 homozygotes versus all other mutations.

^b: Based on a total sample of 140; 8 subjects are missing Meconium ileus status.

^c: Adjusted for population structure, based on the first four principal components.