Table 1 Analyses of candidate reference genes by BestKeeper, GeNorm and NormFinder algorithms

BestKeeper^a

Gene ranking^b

SAND

UK

GAPDH

UBC18

RPL1

UBQ1

ACT

N

24

24

24

24

24

24

24

SD [± CP]

0.21

0.25

0.28

0.38

0.59

1.02

1.04

CV [% CP]

0.72

0.97

1.18

1.28

1.98

2.99

3.24

BestKeeper^c

Gene ranking^b

SAND

UK

GAPDH

UBC18

RPL1

UBQ1

ACT

UK

0.456

–

–

–

–

–

–

0.025

–

–

–

–

–

–

GAPDH

− 0.563

− 0.611

–

–

–

–

–

0.004

0.002

–

–

–

–

–

UBC18

0.473

0.690

− 0.367

–

–

–

–

0.019

0.001

0.078

–

–

–

–

RPL1

0.259

0.163

− 0.393

0.320

–

–

–

0.221

0.444

0.058

0.128

–

–

–

UBQ1

0.151

− 0.126

0.036

− 0.232

− 0.345

–

–

0.479

0.555

0.867

0.275

0.099

–

–

ACT

− 0.330

− 0.419

0.781

− 0.353

− 0.773

0.419

–

0.115

0.041

0.001

0.091

0.001

0.041

–

Coeff. of corr. [r]^d

0.211

− 0.004

0.365

0.130

− 0.299

0.760

0.636

P-value

0.323

0.984

0.079

0.542

0.156

0.001

0.001

BestKeeper^e

SAND

UK

UBC18

Coeff. of corr. [r]

0.705

0.867

0.910

P-value

0.001

0.001

0.001

GeNorm

Gene ranking^b

UBC18

UK

SAND

GAPDH

RPL1

UBQ1

ACT

Stablity (M)

0.224

0.224

0.276

0.578

0.691

1.296

1.343

NormFinder

Gene ranking^b

SAND

UK

GAPDH

UBC18

RPL1

UBQ1

ACT

Stability

0.227

0.274

0.279

0.381

0.539

0.677

0.709

Best gene combination of two genes

SAND

GAPDH

Stability

0.181

0.181