Table 4. Association Status with RA of Our Study and Previous Studies.

	Population	No. of cases	No. of controls	Genotype	Genotype Frequency (cases—controls)	Allele	Allele Frequency (cases—controls)	Association with RA	Reference
MTHFR C677T	Egyptian (our study)	105	80	CC	46–57			Protective
				CT	51–19	T	67–27	Susceptible
	Jewish	93	377					No association	[29]
	Italian	217	251					No association	[5]
	African-American	138	53					No association	[7]
	Caucasian	393	50					No association	[7]
	Turkish	147	150			T	51–32	Susceptible	[30]
MTHFR A1298C	Egyptian (our study)	105	80	AA	46–19			Susceptible
				AC	35–51			Protective
	Jewish	93	377	CC	23–48			Susceptible	[29]
	Italian	217	251	CC	26–12			Susceptible	[5]
	African-American	138	53					No association	[7]
	Caucasian	393	50					No association	[7]
TGFβ1 T869C	Egyptian (our study)	105	80	TC	69–32			Susceptible
				CC	18–29			Protective
	Japanese (Nagoya)	155	110			T	160–101	Susceptible	[31]
	Japanese (Tsukuba)	137	225					No association	[10]
	Chinese	76	100	CC	11–33	C	63–113	Protective	[33]
	Chinese	105	100	CC	17–34	C	86–114	Protective	[34]
	Egyptian (Zagazig)	160	168			T	215–200	Susceptible	[32]
	Turkish	131	133					No association	[35]
	Caucasian (New Zealand)	117	140					No association	[36]
	Caucasian (UK)	395	401					No association	[37]
	Korean	143	148					No association	[38]
ApaI	Egyptian (our study)	105	80	aa (TT)	20–4			Susceptible
	Spanish	120	200					No association	[51]
	Egyptian (Mansoura)	128	150	aa (TT)	26–10			Susceptible	[57]
	Tunisian	106	153					No association	[60]
BsmI	Egyptian (our study)	105	80	bb (GG)	48–19			Susceptible
				BB (AA)	10–20	B (A)	57–81	Protective
	Spanish	120	200					No association	[51]
	Korean	157	211					No association	[52]
	French	96	96					No association	[53]
	Hungarian	64	40					No association	[54]
	Turkish	98	122					No association	[55]
	Tunisian	108	152					No association	[56]
	Egyptian (Mansoura)	128	150	BB (AA)	13–36	B (A)	78–146	Protective	[57]
				bb (GG)	63–40			Susceptible
	Egyptian (Zagazig)	200	150					No association	[58]
	German	62	40					No association	[59]
FokI	Egyptian (our study)	105	80					No association
	French	100	100	FF (CC)	45–30	F (C)	133–108	Susceptible	[53]
	Turkish	98	122					No association	[55]
	Tunisian	108	152	FF (CC)	49–46	F (C)	147–164	Susceptible	[56]
	Egyptian (Mansoura)	128	150					No association	[57]
	German	62	40					No association	[59]
	Canadian	448	704	Ff (CT)	243–308			Susceptible	[62]
	Indian	112	125					No association	[61]
TaqI	Egyptian (our study)	105	80	TT (TT)	48–21	T (T)	143–81	Susceptible
				tt (CC)	10–20			Protective
	Spanish	120	200					No association	[51]
	Korean	157	120					No association	[52]
	French	95	95					No association	[53]
	Turkish	98	122					No association	[55]
	Egyptian (Mansoura)	128	150	TT (TT)	64–39	T (T)	179–152	Susceptible	[57]
				tt (CC)	13–37			Protective
	German	62	40					No association	[59]
	Tunisian	106	153					No association	[60]
TNFB A252G	Egyptian (our study)	105	80	AA	57–22	A	156–87	Susceptible
				AG, GG	42–43, 6–15			Protective
	Belgian	77	58					No association
	Latvian (juvenile RA)	128	114					No association
	Spanish	60	102					No association
	Japanese	60	103					No association
	Caucasian (UK)	388	399	GG	77–47	G	337–283	Susceptible
	Portuguese (White)	388	269	AA	197–117	A	547–346	Susceptible
	Saudi Arabian	106	126	AA, GG	32–15, 27–18			Susceptible
				AG	47–93			Protective
	Tunisian	108	226			G	84–131	Susceptible
				AA	37–115			Protective