Table 4 Results and assessment of cumulative evidence associations (on random effects model) of genetic variants with risk of ASD.

Uddin et al. [44]

CNTNAP2

rs2710102

Allelic

Fixed

0.849 (0.734–0.981)

0.0263

0.0263

0.0

0.711

0.511

0.734–0.981

0.843

Weak

Dominant

Fixed

0.883 (0.681–1.144)

0.3455

0.3494

0.0

0.851

0.848

0.681–1.146

0.731

Non-significant

Heterozygote

Fixed

0.964 (0.736–1.262)

0.7891

0.7896

0.0

0.940

0.946

0.736–1.263

0.700

Non-significant

Homozygote

Fixed

0.668 (0.470–0.950)

0.0248

0.0231

0.0

0.743

0.403

0.467–0.946

0.848

Weak

Recessive

Fixed

0.715 (0.563–0.909)

0.0062

0.0061

0.0

0.632

0.696

0.562–0.909

0.890

Weak

rs7794745

Allelic

Random

1.214 (0.974–1.513)

0.0849

0.0849

72.2

<0.001

0.487

0.689–2.137

0.009

Non-significant

Dominant

Fixed

1.300 (1.109–1.523)

0.0012

0.0081

32.2

0.171

0.442

0.895–1.914

0.718

Weak

Heterozygote

Fixed

1.275 (1.081–1.504)

0.0039

0.0066

8.8

0.362

0.637

1.010–1.612

0.288

Weak

Homozygote

Random

1.490 (0.776–2.859)

0.2309

0.2309

72.5

<0.001

0.185

0.277–7.999

<0.001

Non-significant

Recessive

Random

1.301 (0.692–2.444)

0.4140

0.4140

73.4

<0.001

0.150

0.253–6.684

0.001

Non-significant

Yang et al. [39]

COMT

rs4680

Allelic

Random

0.993 (0.779–1.265)

0.9534

0.9534

61.1

0.053

0.570

0.642–1.534

0.041

Non-significant

Noroozi et al. [52]

GABRB3

rs20317

Allelic

Fixed

0.917 (0.781–1.076)

0.2875

0.2878

0.0

0.968

0.605

0.781–1.076

0.712

Non-significant

Dominant

Random

1.037 (0.699–1.538)

0.8574

0.8574

51.6

0.127

0.064

0.557–1.924

0.670

Non-significant

Heterozygote

Random

1.173 (0.682–2.015)

0.5647

0.5647

70.8

0.033

0.010

0.436–3.194

0.014

Non-significant

Homozygote

Fixed

0.939 (0.654–1.347)

0.7304

0.7905

31.6

0.232

0.869

0.650–1.357

0.661

Non-significant

Recessive

Fixed

0.827 (0.624–1.098)

0.1887

0.2492

22.8

0.274

0.467

0.568–1.197

0.733

Non-significant

rs4906902

Allelic

Fixed

1.042 (0.924–1.175)

0.5010

0.5113

5.1

0.378

0.834

0.844–1.293

0.715

Non-significant

Dominant

Fixed

1.046 (0.897–1.219)

0.5671

0.6350

25.3

0.253

0.930

0.762–1.436

0.710

Non-significant

Heterozygote

Fixed

1.034 (0.879–1.215)

0.6873

0.7338

23.2

0.267

0.931

0.750–1.425

0.703

Non-significant

Homozygote

Fixed

1.066 (0.807–1.408)

0.6547

0.6584

0.0

0.766

0.502

0.806–1.408

0.704

Non-significant

Recessive

Fixed

1.071 (0.819–1.399)

0.6171

0.6205

0.0

0.930

0.624

0.818–1.399

0.706

Non-significant

Li et al. [33]

MTHFR

A1298C

Allelic

Random

1.260 (0.949–1.674)

0.1101

0.1101

85.0

<0.001

0.045

0.341–5.411

<0.001

Non-significant

Dominant

Random

1.255 (0.895–1.759)

0.1887

0.1887

80.5

<0.001

0.016

0.298–6.898

<0.001

Non-significant

Heterozygote

Random

1.163 (0.838–1.615)

0.3674

0.3674

75.3

<0.001

0.017

0.375–4.221

<0.001

Non-significant

Homozygote

Random

1.377 (0.847–2.237)

0.1969

0.1969

72.1

<0.001

0.129

0.340–5.947

0.052

Non-significant

Recessive

Random

1.198 (0.769–1.867)

0.4241

0.4241

70.3

<0.001

0.379

0.365–3.993

0.016

Non-significant

Zhang et al. [36]

MTHFR

C677T

Allelic

Random

1.799 (1.303–2.483)

0.0004

0.0004

83.6

<0.001

0.003

0.545–5.942

0.072

Suggestive

Dominant

Random

1.959 (1.402–2.738)

<0.0001

8.17E-05

76.2

<0.001

0.004

0.596–6.435

0.190

Suggestive

Heterozygote

Random

1.767 (1.343–2.330)

<0.0001

5.01E-05

64.2

<0.001

0.004

0.717–4.365

0.222

Suggestive

Homozygote

Random

1.795 (1.158–2.782)

0.0089

0.0089

64.2

<0.001

0.008

0.489–6.584

0.005

Weak

Recessive

Random

1.424 (0.980–2.069)

0.0634

0.0634

60.0

0.001

0.012

0.497–4.085

0.002

Non-significant

Zhou [47]

OXTR

rs2254298

Allelic

Random

1.056 (0.810–1.379)

0.6863

0.6863

65.8

0.020

0.158

0.585–1.874

0.381

Non-significant

rs2301261

Allelic

Random

1.002 (0.617–1.627)

0.9943

0.9943

59.4

0.085

0.555

0.459–2.195

0.677

Non-significant

rs53576

Allelic

Fixed

1.103 (0.978–1.244)

0.1109

0.1341

36.1

0.195

0.273

0.862–1.498

0.776

Non-significant

Chen et al. [49]

RELN

rs607755

Allelic

Fixed

1.316 (1.029–1.683)

0.0284

0.0661

32.7

0.226

0.397

1.028–1.683

0.353

Non-significant

Dominant

Fixed

1.520 (1.061–2.178)

0.0226

0.0648

31.5

0.232

0.176

0.810–3.334

0.348

Non-significant

Heterozygote

Fixed

1.483 (1.016–2.165)

0.0411

0.0590

7.5

0.339

0.057

0.859–2.785

0.811

Non-significant

Homozygote

Fixed

1.816 (1.051–3.136)

0.0324

0.0841

40.9

0.184

0.243

1.030–3.120

0.320

Non-significant

Recessive

Fixed

1.317 (0.831–2.086)

0.2411

0.2890

18.6

0.293

0.314

0.818–2.079

0.717

Non-significant

Hernández-García et al. [50]

RELN

rs2229864

Allelic

Random

0.809 (0.547–1.198)

0.2896

0.2896

78.3

0.003

0.675

0.381–1.715

0.540

Non-significant

Dominant

Fixed

0.783 (0.500–1.227)

0.2856

0.6264

47.4

0.127

0.186

0.279–2.595

0.114

Non-significant

Heterozygote

Fixed

0.981 (0.610–1.577)

0.9376

0.9397

0.0

0.547

0.150

0.607–1.588

0.677

Non-significant

Homozygote

Random

0.772 (0.341–1.744)

0.5334

0.5334

64.6

0.037

0.246

0.178–3.324

0.238

Non-significant

Recessive

Random

0.747 (0.480–1.160)

0.1939

0.1939

73.9

0.009

0.903

0.322–1.729

0.547

Non-significant

rs362691

Allelic

Fixed

0.958 (0.771–1.189)

0.6948

0.6826

6.0

0.378

0.631

0.662–1.355

0.719

Non-significant

Dominant

Fixed

0.838 (0.580–1.211)

0.3477

0.3352

0.0

0.538

0.255

0.572–1.210

0.746

Non-significant

Heterozygote

Fixed

0.803 (0.550–1.174)

0.2580

0.2624

0.0

0.559

0.168

0.545–1.180

0.756

Non-significant

Homozygote

Fixed

1.399 (0.666–2.937)

0.3749

0.4116

0.0

0.720

0.969

0.648–2.821

0.736

Non-significant

Recessive

Fixed

1.033 (0.773–1.381)

0.8260

0.8336

0.0

0.415

0.744

0.704–1.509

0.715

Non-significant

rs736707

Allelic

Random

0.975 (0.765–1.243)

0.8391

0.8391

68.8

0.007

0.178

0.565–1.682

0.001

Non-significant

Dominant

Random

0.979 (0.696–1.377)

0.9034

0.9034

61.8

0.023

0.494

0.472–2.031

0.001

Non-significant

Heterozygote

Random

1.012 (0.819–1.249)

0.9157

0.9576

38.1

0.152

0.513

0.577–1.699

0.713

Non-significant

Homozygote

Random

0.996 (0.626–1.584)

0.9869

0.9869

62.9

0.019

0.178

0.360–2.748

0.002

Non-significant

Recessive

Fixed

1.056 (0.844–1.320)

0.6353

0.8826

36.3

0.165

0.053

0.606–1.722

0.723

Non-significant

Wang et al. [40]

SLC6A4

5-HTTLPR

Allelic

Random

1.138 (0.849–1.526)

0.3878

0.3878

76.1

<0.001

0.511

0.508–2.546

0.003

Non-significant

Dominant

Random

1.201 (0.886–1.644)

0.2337

0.2337

45.1

0.059

0.125

0.638–2.248

0.810

Non-significant

Heterozygote

Random

1.125 (0.776–1.631)

0.5346

0.5346

50.7

0.032

0.035

0.535–2.244

0.237

Non-significant

Homozygote

Random

1.358 (0.730–2.525)

0.3341

0.3341

79.7

<0.001

0.913

0.268–6.859

0.519

Non-significant

Recessive

Random

1.110 (0.617–2.000)

0.7274

0.7274

85.7

<0.001

0.852

0.186–6.611

0.025

Non-significant

Sun [55]

VDR

rs11568820

Allelic

Fixed

1.050 (0.893–1.234)

0.5577

0.6390

36.2

0.195

0.964

0.723–1.533

0.054

Non-significant

Dominant

Fixed

1.028 (0.834–1.266)

0.7969

0.9115

43.1

0.153

0.733

0.605–1.704

0.037

Non-significant

Heterozygote

Fixed

0.992 (0.794–1.240)

0.9445

0.8981

40.1

0.171

0.628

0.584–1.640

0.677

Non-significant

Homozygote

Fixed

1.118 (0.781–1.600)

0.5435

0.5500

0.0

0.631

0.710

0.779–1.598

0.694

Non-significant

Recessive

Fixed

1.150 (0.819–1.616)

0.4191

0.4224

0.0

0.843

0.537

0.818–1.615

0.707

Non-significant

rs1544410

Allelic

Fixed

1.069 (0.923–1.239)

0.3730

0.3734

0.0

0.988

0.080

0.923–1.239

0.728

Non-significant

Dominant

Fixed

1.043 (0.840–1.296)

0.7021

0.7022

0.0

0.824

0.991

0.840–1.296

0.702

Non-significant

Heterozygote

Fixed

0.996 (0.792–1.252

0.9709

0.9707

0.0

0.451

0.931

0.675–1.475

0.696

Non-significant

Homozygote

Fixed

1.162 (0.840–1.607)

0.3642

0.3647

0.0

0.894

0.347

0.840–1.604

0.729

Non-significant

Recessive

Fixed

1.166 (0.894–1.522)

0.2565

0.2619

0.0

0.430

0.535

0.837–1.609

0.159

Non-significant

rs2228570

Allelic

Fixed

1.002 (0.879–1.143)

0.9736

0.9688

29.5

0.203

0.492

0.804–1.245

0.130

Non-significant

Dominant

Fixed

0.927 (0.770–1.116)

0.4243

0.4322

30.3

0.197

0.441

0.691–1.226

0.178

Non-significant

Heterozygote

Fixed

0.873 (0.719–1.060)

0.1712

0.2073

13.9

0.324

0.473

0.710–1.078

0.268

Non-significant

Homozygote

Random

1.138 (0.714–1.814)

0.5857

0.5857

45.9

0.085

0.596

0.494–2.600

0.741

Non-significant

Recessive

Fixed

1.157 (0.902–1.486)

0.2516

0.3434

30.7

0.193

0.313

0.728–1.854

0.206

Non-significant

rs731236

Allelic

Fixed

1.297 (1.125–1.494)

0.0003

0.0003

0.0

0.675

0.293

1.125–1.494

0.436

Suggestive

Dominant

Fixed

1.304 (1.082–1.571)

0.0053

0.0274

33.3

0.186

0.839

0.897–1.913

0.208

Weak

Heterozygote

Random

1.203 (0.864–1.674)

0.2739

0.2739

60.1

0.028

0.933

0.588–2.461

0.049

Non-significant

Homozygote

Fixed

1.741 (1.258–2.409)

0.0008

0.0009

0.0

0.466

0.178

1.109–2.803

0.708

Suggestive

Recessive

Fixed

1.613 (1.187–2.190)

0.0022

0.0160

40.2

0.153

0.242

0.807–3.528

0.256

Weak

rs7975232

Allelic

Fixed

0.823 (0.681–0.993)

0.0425

0.0817

24.4

0.266

0.931

0.587–1.136

0.310

Non-significant

Dominant

Fixed

0.740 (0.536–1.022)

0.0677

0.0690

0.0

0.614

0.390

0.536–1.024

0.794

Non-significant

Heterozygote

Fixed

0.759 (0.540–1.066)

0.1118

0.1168

0.0

0.834

0.014

0.542–1.071

0.766

Non-significant

Homozygote

Random

0.528 (0.218–1.276)

0.1558

0.1558

58.3

0.091

0.615

0.119–2.306

0.300

Non-significant

Recessive

Random

0.735 (0.404–1.337)

0.3137

0.3137

65.5

0.055

0.663

0.263–2.053

0.152

Non-significant