Interleukin-17 SNPs and serum levels increase ulcerative colitis risk: A meta-analysis

Table 1 Baseline characteristics and methodological quality of the included studies focused on IL-17A/F genetic polymorphisms

Ref.	Year	Country	Ethnicity	Number		Gender (M/F)		Age (yr)		Genotyping method	Genetype	NOS score
				Case	Control	Case	Control	Case	Control
Yu et al[42]	2012	China	Asian	270	268	130/140	136/132	47.4 ± 14.1	47.1 ± 12.9	PCR-LDR	IL-17A/F	8
Hayashi et al[10]	2012	Japan	Asian	202	475	114/88	241/234	41.1 ± 14.3	59.4 ± 12.7	PCR-SSCP	IL-17A	8
Kim et al[41]	2011	South Korea	Asian	268	258	-	-	-	-	Direct sequencing	IL-17A	6
Chen[40]	2009	China	Asian	148	373	83/65	233/140	38.4 ± 12.9	37.9 ± 16.1	PCR-RFLP	IL-17F	8
Seiderer et al[26]	2008	Germany	Caucasian	216	967	110/106	609/358	42.6 ± 14.8	47.4 ± 11.3	PCR-RFLP	IL-17F	8
Arisawa et al[39]	2008	Japan	Asian	111	248	56/55	133/115	39.0 ± 14.3	46.6 ± 18.4	PCR-SSCP	IL-17A/F	7

F: Female; LDR: Ligase detection reaction; M: Male; NOS: Newcastle-Ottawa Scale; PCR: Polymerase chain reaction; RFLP: Restriction fragment length polymorphism; SSCP: Single-strand conformation polymorphism.

Table 2 Baseline characteristics and methodological quality of the included studies focused on serum interleukin-17 levels

Ref.	Year	Country	Ethnicity	Number		Gender (M/F)		Age (yr)		Detection method	NOS score
				Case	Control	Case	Control	Case	Control
Ohman et al[14]	2013	China	Asian	99	10	70/29	4/6	32	48	ELISA	6
Liu[38]	2013	China	Asian	20	30	-	-	-	-	ELISA	7
Lin et al[37]	2012	China	Asian	50	50	22/28	25/25	38.0 ± 6.0	37.0 ± 5.0	ELISA	7
Chen[36]	2012	China	Asian	24	20	10/14	7/13	37.6 ± 9.4	38.9 ± 9.9	ELISA	7
Zhen et al[35]	2011	China	Asian	54	30	30/24	19/11	40.9 ± 8.3	50.6 ± 5.3	ELISA	7
Luo et al[34]	2011	China	Asian	24	30	14/10	17/13	-	-	ELISA	8
Xin et al[33]	2010	China	Asian	29	26	18/11	13/13	41.4 ± 9.6	32.0 ± 11.2	ELISA	6
He et al[32]	2010	China	Asian	25	10	12/13	-	-	-	ELISA	8
Rovedatti et al[31]	2009	United Kingdom	Caucasian	34	38	-	-	35.6 (14-53)	-	ELISA	8
Liang et al[30]	2005	China	Asian	40	30	28/12	19/11	41.5 ± 12.0	41.3 ± 12.0	ELISA	8

F: Female; M: Male; NOS: Newcastle-Ottawa Scale.