Table 3.

HI3L1 genotypes and the effect on serum YKL-40 levels in patients with rheumatoid arthritis and controls.

SNP	CHI3L1 position	Controls (n = 605)	F df = 603	P-value	RA age ≤ 65 years (n = 238)	F Df = 236	P-value
rs6691378	g.-1371G/A	Serum YKL-40 ng/ml			serum YKL-40 ng/ml
	G/G	46 (44 to 48)	6.63	0.0014	67 (61 to 74)	2.85	0.06
	G/A	54 (50 to 59)			77 (62 to 95)
	A/A	47 (34 to 68)			151 (71 to 323)
rs10399931	g.-329C/T
	C/C	56 (53 to 58)	83.13	< 2.2e-16	80 (71 to 89)	12.34	8.0e-06
	C/T	40 (38 to 42)			61 (53 to 70)
	T/T	25 (22 to 29)			35 (24 to 49)
rs10399805	g.-247G/A
	G/G	45 (44 to 47)	7.47	6.3e-3	67 (61 to 74)	2.69	0.07
	G/A	54 (50 to 59)			76 (61 to 94)
	A/A	48 (34 to 68)			151 (71 to 323)
rs4950928	g.-131C/G
	C/C	56 (53 to 58)	102.32	< 2.2e-16	81 (73 to 90)	18.91	2.4e-08
	C/G	38 (38 to 40)			59 (51 to 68)
	G/G	25 (22 to 28)			31 (22 to 43)
rs7515776	g.+48A/T
	A/A	46 (44 to 48)	7.02	9.7e-3	67 (61 to 74)	1.76	0.17
	A/T	54 (50 to 59)			77 (62 to 95)
	T/T	48 (33 to 70)			119 (62 to 231)
rs1538372	g.+1219G/A
	G/G	56 (53 to 59)	46.93	< 2.2e-16	78 (68 to 89)	7.58	6.5e-3
	G/A	43 (41 to 45)			69 (60 to 78)
	A/A	34 (30 to 37)			45 (34 to 57)
rs2071579	g.+2117G/C
	C/C	56 (52 to 59)	21.91	6.5e-10	72 (62 to 84)	6.31	0.0022
	C/G	47 (44 to 49)			76 (67 to 86)
	G/G	39 (36 to 42)			52 (43 to 62)
rs880633	g.+2950C/T
	C/C	56 (52 to 59)	21.91	6.7e-10	72 (62 to 84)	6.31	0.0022
	C/T	47 (44 to 49)			76 (67 to 86)
	T/T	39 (36 to 42)			52 (43 to 62)

Serum concentrations of YKL-40 are given as median ± 95% CI.

CHI3L1, chitinase 3-like 1 gene; CI, confidence interval; RA, rheumatoid arthritis; SNP, single nucleotide polymorphism.