TABLE 1.

Overview of 9 case-control studies of G/A alleles and GG/AA+AG genotypes.

Study	Group	n	AA	AG	GG	A	G	χ2 P Value
Rivera 1997	EEA (E)	124	61	47	16	169	79	0.283
	Controls	115	63	42	10	168	62
Muniesa 2008	Rowers (E+P)	39	15	18	6	48	30	0.208
	Cyclists (E)	50	23	23	4	69	31
	Runners (E)	52	22	28	2	72	32
	Controls	123	43	65	15	151	95
Ruiz 2009	EEA (E)	46	21	20	5	62	30	0.372
	Controls	123	43	65	15	151	95
Fedotovskaya 2012	Boat racing (E+P)	95	43	34	18	120	70	0.661
	Biathlon (E)	51	26	21	4	73	29
	Skating_5-10 km (E)	13	10	3	0	23	3
	Jumping race (P)	68	42	20	6	104	32
	Cross-country skiing_5-15 km (E)	44	27	15	2	69	19
	Weightlifting (P)	74	29	22	23	80	68
	Soccer	39	19	16	4	54	24
	Controls	1116	493	473	150	1459	773
Fedotovskaya 2013	Judo (P)	29	10	11	8	31	27	0.055
	Wrestling (P)	79	29	35	15	93	65
	Boxing (P)	51	19	25	7	63	39
	Controls	1512	637	674	201	1948	1076
Eider 2015	Rowers (E+P)	220	97	93	30	287	153	0.364
	Controls	1854	845	813	196	2503	1205
Grealy 2015	EET (E)	196	93	83	20	269	123	0.290
	Controls	113	58	49	6	165	61
He 2016	Endurance (E)	35	20	14	1	54	16	0.681
	Speed Power (P)	43	19	13	11	51	35
	Uyghur Soccer	36	17	13	6	47	25
	Controls	441	214	175	52	603	279
Yvert 2016	Runners (E)	175	126	49	0	301	49	0.523
	Controls	649	465	166	18	1096	202

2 test is performed between all athletes and controls for allele G and A.

EEA is short for Elite Endurance Athlete.

E is short for Endurance Sport.

P is short for Power Sport.