Table 2. Studies Reporting Significant Main Effects for Candidate Gene Studies.

Genetic variants associating with PTB risk as main effects are reported by gene if five or more studies reported any type of significant association, including main effects, genetic risk score, haplotype, and SNP-SNP interaction associations. For each genetic variant, study population and direction of effect relative to the minor allele are reported unless noted otherwise.

Gene	SNPs/Genetic Locus	Population	Reference and Effecta
CD209/DC-SIGN
	rs4804803	Iranian	[89] +
		West African	[27] −
	rs735240	Indonesian	[90] −
HLA-A
	HLA-A*02	Chinese	[91] +
	HLA-A*24	Chinese	[91] +
	HLA-A*26	Iranian	[92] +
	HLA-A*32	Indian (Sahariya)	[93] +
	HLA-A-R114	Greek	[94] +
HLA-DQB1
	HLA-DQB1*02	Polish	[95] −
	HLA-DQB1*0201	Polish	[96] −
	HLA-DQB1*0301	Thai	[97] −
	HLA-DQB1*0303	Indian	[98] −
	HLA-DQB1*05	Pole	[95] +
	HLA-DQB1*0502	Thai	[97] +
	HLA-DQB1*050301	Indian	[98] +
	HLA-DQB1*0601	Indian	[98] +
		Korean	[99] +
	HLA-DQB1*1502	Indian	[100] −
	HLA-DQB1*1601	Polish	[96] +
HLA-DRB1
	HLA-DRB1*04	Brazilian	[101] +
	HLA-DRB1*04:07:01	Amazonian	[102] −
	HLA-DRB1*04:11:01	Amazonian	[102] +
	HLA-DRB1*04:92	Amazonian	[102] +
	HLA-DRB1*0601	Korean	[99] +
	HLA-DRB1*07	Iranian	[92] +
	HLA-DRB1*0803	Korean	[99] +
	HLA-DRB1*1302	South African	[103] +
	HLA-DRB1*14	Portuguese	[104] +
	HLA-DRB1*15	Brazilian	[101] −
		Chinese	[105] +
		Indian (Sahariya)	[93] +
	HLA-DRB1*1502	Indian	[101] +
	HLA-DRB1*16	Chinese	[91] +
		Indian (Sahariya)	[93] −
	HLA-DRB1*1601	Polish	[96] +
	HLA-DRB1-N37	Greek	[94] +
IFNG
	CA repeats	Chinese	[106] -e
	rs1861493	Indian	[107] −
	rs1861494	Chinese	[108] −
		Indian	[107] −
	rs2069705	West African	[28] −
	rs2069718	West African	[28] −
	rs2430561	Iranian	[109] −
		Sicilian	[110] −
		Spaniard	[111] −
		Tunisian	[112] −
IFNGR1
	-56 T/C	West African	[28] +
	rs1327475	Chinese	[113] +
	rs2234711	Chinese	[113] +
	rs7749390	Chinese	[113] −
	rs489243	Ugandan	[24] −
	CA repeats	Indonesian	[114] +e
		Ugandans	[24] +
IL10
	rs1800871	Chinese	[115] −
	rs1800872	Chinese	[106] −
		Korean	[116] −
	rs1800896	Cambodian	[117] +
		Korean	[118] −
		Sicilian	[119] b
MBL2
	Exon 1 ”AO”	Brazilian	[120] +
		Brazilian	[121] +
	rs11003125	Chinese	[122] −
	rs1800451	Brazilian	[120] +
	rs7096206	Brazilian	[120] +
MCP1
	-11822 G/A	Ghanaian	[123] −
	rs1024611	Chinese	[124] +
		Chinese	[125] +
		Ghanaian	[126] −
		Ghanaian	[123] −
		Korean	[127] +
		Mexican	[127] +
		Moroccan	[128] −
		Tunisian	[129] +
	-1549 A/T	Ghanaian	[123]b
	rs2857656	Ghanaian	[126] −
		Ghanaian	[123] −
	+900 C/T	Ghanaian	[123]b
	rs3917887	Ghanaian	[126] −
	+5356 C/T	Ghanaian	[123] −
NRAMP1/SLC11A1
	(GT)n Allele 2	Gambian	[130] +f
	(GT)n Allele 3	Gambian	[130] -g
		Polish	[131] +h
	5′(GT)n Allele 9	South African	[132]i
	rs17221959	Indian	[133] −
	rs17235409	Cambodian	[117]b
		Chinese	[134] +c
		Chinese	[135] +
		Peruvian	[136] b
		Tunisian	[137] +
	rs17235416	Cambodian	[117] b
		Chinese	[135] +
		Chinese	[122] +
		Indian	[133] +
		Indonesian	[138] +
		South African	[132] +
		Tunisian	[137] +
		Chinese	[134] +c
	rs3731865	Chinese	[139] +
		Indian	[133] +
		Peruvian	[136] +
TLR2
	-196 to -174 del	Pakistan	[140] +
		Guinea-Bissauan	[21] −
	GTn repeats in intron 2	Chinese	[141] +j
		Chinese	[141] -k
	rs121917864	Tunisian	[142] +
	rs3804099	Chinese	[143] +d
		Iranian	[144] +
		Moroccan	[145]b
TLR4
	rs11536889	Moroccan	[145] +
	rs1927906	Sudanese	[146] +
	rs1927911	Sudanese	[146] +
	rs4986790	Indian	[147] +
		Tanzanian	[148] +
	rs4986791	Indian	[147] +
	rs5030725	Sudanese	[146] +
	rs7869402	Sudanese	[146] +
TLR9
	rs352139	Chinese	[108] +
	rs352140	Aché	[149] +
		Chinese	[108] +
	rs352143	Vietnamese	[150] +
TNF
	rs1799724	Chinese	[151] −
	rs1800629	Chinese	[152] +
		Colombian	[153] −
		Iranian	[154] +
		Mozambican	[155] +
		Sicilian	[119] +
	rs1800630	Chinese	[151] +
	rs361525	Colombian	[153] +
		Iranian	[156] −
VDR
	rs1544410	Indian	[157] +
		Indonesian (Batak)	[158] −
		Iranian	[154] −
		Iranian	[159] +
		Iranian	[160]−
	rs2228570	Chinese	[122] +
		Chinese	[135] +
		Indians	[161] +
		Indians	[162] +
		Iranian	[160] −
	rs731236	Chinese	[122] −
		Indian	[163] −
		Indian	[164] +
		Indian	[162] +
		Iranian	[159] +
	rs7975232	Indian	[163] +
		Indian	[162] −
		West African	[26] −

^aWhen the minor allele associated with increased risk, + was reported for effect, while - was reported when the minor allele associated with decreased risk. Direction of effect was reported based on allelic and/or genotypic associations.

^bDenotes associations where only heterozygotes associated with PTB risk.

^cIndicates the association with PTB risk was only found in women.

^dIndicates the association with PTB risk was only found in men.

^eDirection of effect is relative to non-12 CA repeats

^fDirection of effect is relative to non-allele 2

^gAllele 3 associated with decreased risk

^hAllele 3 associated with increased risk

ⁱDirection of effect is relative to non 5′ (GT)₉ alleles

^jS/M genotype associated with increased risk

^kS/L genotype associated with decreased risk