Table II.

Ratio of Arabidopsis genes in OGs that expanded via tandem duplication and nontandem mechanisms

OG TypeMethod for Defining OGExpansion PatternPc
ConvergentaSingle-Lineageb
A-MSimilarity0.17 (756/4,500)0.30 (848/2,918)2.2 × 10−23
Tree0.16 (831/5,297)0.40 (1,443/3,566)9.4 × 10−88
A-RSimilarity0.31 (959/3,115)0.47 (644/1,375)3.1 × 10−12
Tree0.27 (844/3,073)0.50 (1,631/3,294)2.3 × 10−33
A-PSimilarity0.29 (1,141/3,944)0.60 (741/1,234)7.2 × 10−38
Tree0.26 (1,014/3,930)0.64 (1,578/2,452)1.0 × 10−83
  • a OGs showing convergent expansion are defined based on the presence of more than two genes in both lineages. In the parentheses, the numerator is the number of genes in OGs expanded via tandem duplication and the denominator is the number of genes in OGs expanded via nontandem mechanisms.

  • b OGs showing single-lineage expansion are defined as having two or more genes in the Arabidopsis lineage and zero in the other. Numbers in parentheses are as described above.

  • c The ratios of tandem to nontandem duplicates in OGs experiencing convergent and single-lineage expansion were compared using χ2 tests.