TABLE 1

Levels of codon bias in genes with male-, female-, and non-sex-biased expression

CutoffaMaleFemaleNon-sexPMFbPMNbPFNb
N1.5196322902987
ENC1.548.5048.2147.851.6 × 10−92.3 × 10−200.005
FOP1.50.5190.5410.5377.1 × 10−113.9 × 10−110.645
N2.0129314434535
ENC2.050.3248.0447.997.7 × 10−71.7 × 10−320.186
FOP2.00.5070.5440.5373.5 × 10−183.1 × 10−230.299
N3.08605645851
ENC3.051.1147.1848.137.2 × 10−212.1 × 10−390.087
FOP3.00.4960.5580.5362.7 × 10−225.0 × 10−320.002
  • a Fold expression cutoff used to classify sex-biased genes.

  • b P-value of two-tailed Mann-Whitney test for comparisons among male- (M), female- (F), and non-sex-biased (N) genes.

  • N, number of genes; ENC, effective number of codons (Wright 1990); FOP, frequency of optimal codons (Ikemura 1981). Numbers represent the mean value for each category.