Aryl hydrocarbon receptor rs2066853 gene polymorphisms and male infertility risk: a meta-analysis

Figures & data

Figure 1. Flowchart of the study selection procedure.

Table 1. Main characteristics of studies included in the meta-analysis.

Study/year	Country	Genotypingmethod	Case	Control	Case					Control					HWE
					GG	GA	AA	G	A	GG	GA	AA	G	A
Aftabi et al. 2017	Iran	PCR-RFLP	135	130	68	62	5	198	72	73	53	4	199	61	0.120
Gu et al. 2011	China	TaqMan	567	573	255	231	81	741	393	249	244	80	742	404	0.108
Liu et al. 2016	China	PCR	136	456	58	57	18	173	93	193	206	55	592	316	0.998
Merisalu et al. 2007	Estonia	ASPCR	110	211	96	14	0	206	14	175	36	0	386	36	0.195
Mostafa et al. 2017	Egypt	Real-time PCR	120	50	43	21	56	107	133	28	15	7	71	29	0.055
Safarinejad et al. 2013	Iran	PCR	176	352	73	89	14	235	117	131	152	69	414	290	0.710
Watanabe et al. 2004	Japan	PCR	123	112	36	64	23	136	110	32	58	22	122	102	0.641

Table 2. Quality assessment for all of the included studies.

First author	Publishing year	Selection	Comparability	Exposure	Total
Aftabi et al.	2017	★★	★★	★★	6
Gu et al.	2011	★★★	★	★★	6
Liu et al.	2016	★★★	★	★★	6
Merisalu et al.	2007	★★	NA	★★	4
Mostafa et al.	2017	★★	★	★★	5
Safarinejad et al.	2013	★★	★★	★★	6
Watanabe et al.	2004	★★	★	★★	5

Figure 2. Forest plot of the studies assessing the association between AHR rs2066853 gene polymorphisms and male infertility based on allelic model (allele model: A vs. G).

Figure 3. Forest plot of the studies assessing the association between AHR rs2066853 gene polymorphisms and male infertility based on additive model (additive model: AA vs. GG).

Figure 4. Forest plot of the studies assessing the association between AHR rs2066853 gene polymorphisms and male infertility based on recessive model (recessive model: AA vs. GG + GA).

Figure 5. Forest plot of the studies assessing the association between AHR rs2066853 gene polymorphisms and male infertility based on dominant model (dominant model: AA + GA vs. GG).

Table 3. Meta-analysis of the association of AHR rs2066853 gene polymorphisms with male infertility.

	N	A vs. G		AA vs. GG		AA vs. GA + GG		AA + GA vs. GG
		OR	PH	OR	PH	OR	PH	OR	PH
Total	7	1.06 [0.81–1.38]	<0.05	1.10 [0.61–1.97]	<0.05	1.10 [0.61–1.98]	<0.05	0.98 [0.84–1.13]	0.180
Ethnicity
Asian	3	0.98 [0.86–1.12]	0.980	1.00 [0.75–1.33]	0.940	1.03 [0.79–1.34]	0.930	0.94 [0.78–1.13]	0.990
European	3	0.85 [0.60–1.22]	0.100	0.61 [0.17–2.11]	0.090	0.56 [0.18–1.82]	0.100	0.92 [0.71–1.21]	0.290
African	1	3.04 [1.84–5.02]	–	5.21 [2.08–13.05]	–	5.38 [2.24–12.90]	–	2.28 [1.16–4.46]	–
OA	2	2.52 [1.72–3.70]	0.230	4.66 [2.22–9.80]	0.620	3.99 [2.09–7.61]	0.170	2.36 [1.35–4.13]	0.870

PH: P value for heterogeneity; OA: oligoasthenotspermia.

Figure 6. Funnel plot of the studies assessing the association between AHR rs2066853 gene polymorphisms and male infertility (allele model: A vs. G; additive model: AA vs. GG; recessive model: AA vs. GG + GA; dominant model: AA + GA vs. GG).

Figure 7. Sensitivity analysis diagram for each study used to assess the relative risk estimates for the AHR rs2066853 gene polymorphisms and male infertility in all the included studies (allele model: A vs. G; additive model: AA vs. GG; recessive model: AA vs. GG + GA; dominant model: AA + GA vs. GG).

Table 4. Publication bias test for the AHR rs2066853 gene polymorphism.

Comparisons	Egger’s test			Begg’s test
	Coefficient	p Value	95 % CI	p Value
A vs. G	0.273	.871	−3.823 to 4.369	.548
AA vs. GG	1.125	.760	−8.412 to 10.662	.452
AA vs. GA + GG	0.049	.970	−3.329 to 3.426	.452
AA + GA vs. GG	−1.354	.727	−10.790 to 8.083	.368