. 2019 Jul 23;12:1201–1212. doi: 10.2147/DMSO.S205379

Table 1.

The genotypic and allelic distributions of MTHFR C677T for cases and controls

First author	Year	Country	Ethnicity	Age range	Genotype distribution						Allele frequency				P-value HWE	Number of cases/controls
First author	Year	Country	Ethnicity	Age range	Cases			Controls			Cases		Controls		P-value HWE	Number of cases/controls
CC	CT	TT	CC	CT	TT	C	T	C	T
Glueck²⁴	2003	America	White	Adults	13	12	3	5	5	0	38	18	15	5	0.292	28/10
Terruzzi⁹	2007	Italy	White	Adults	18	54	12	14	33	5	90	78	61	43	0.026	84/52
Lewis(BWHHS)¹¹	2008	UK	White	Adults	360	410	112	1165	1086	283	1130	634	3416	1652	0.214	882/2543
Lewis(ALSPAC for women)¹¹	2008	UK	White	Adults	163	155	38	2707	2713	715	481	231	8127	4143	0.375	356/6135
Lewis(ALSPAC for children)¹¹	2008	UK	White	Children	115	93	25	2155	2190	552	323	143	6500	3294	0.902	233/4897
Lewis(CCHS)¹¹	2008	Denmark	White	Adults	588	574	107	3812	3356	736	1750	788	10,980	4828	0.946	1269/7904
Settin²⁵	2009	Saudi	Asian	Adults	89	34	5	69	36	5	212	44	174	46	0.912	128/110
Tavakkoly Bazzaz²⁶	2010	Iran	Asian	Adults	44	21	9	113	80	14	109	39	306	108	0.975	74/207
Gara²⁸	2011	Tunisian	African	Children	15	14	2	9	12	1	44	18	30	14	0.228	31/22
Bokor²⁷	2011	France	White	Children	97	99	17	130	154	33	293	133	414	220	0.2	213/317
Tabassum³⁰	2012	Indian	Asian	Children	290	144	20	581	218	31	724	184	1380	280	0.068	454/830
Yin³¹	2012	China	Asian	Adults	354	341	56	471	441	66	1049	453	1383	573	0.006	751/978
Chauhan²⁹	2012	Indian	Asian	Adults	348	185	29	272	148	16	881	243	692	180	0.451	562/436
Hernandez-Guerrero³²	2013	Mexico	Mestizo	Adults	18	38	19	15	28	10	74	76	58	48	0.63	75/53
Fan³³	2015	China	Asian	Adults	115	244	158	160	375	206	474	560	695	787	0.662	517/741
Chedraui³⁴	2016	Ecuador	White	Adults	51	43	17	35	39	7	145	77	109	53	0.399	111/81
Kupcinskiene³⁵	2016	Lithuania	White	Adults	156	135	28	159	129	15	447	191	447	159	0.082	319/303
Shen³⁶	2016	Canada	White	Adults	190	182	51	181	212	53	562	284	574	318	0.447	423/446
Zhi³⁷	2016	China	Asian	Adults	287	633	434	198	438	249	1207	1501	834	936	0.838	1354/885
Fu³⁸	2018	China	Asian	Children	121	364	273	531	1353	861	606	910	2415	3075	0.99	758/2745

Abbreviations: MTHFR, methylenetetrahydrofolate reductase; HWE, Hardy-Weinberg equilibrium test; The P-value for HWE testing for controls is shown; BWHHS, British Women’s Heart and Health Study; ALSPAC, Avon Longitudinal Study of Parents and Children women cohort study; CCHS, Copenhagen City Heart Study.