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In an effort to identify newly evolved genes in rice, we searched the genomes of Asian-cultivated rice Oryza sativa ssp. japonica and its wild progenitors, looking for lineage-specific genes. Using genome pairwise comparison of approximately 20-Mb DNA sequences from the chromosome 3 short arm (Chr3s) in six rice species, O. sativa, O. nivara, O. rufipogon, O. glaberrima, O. barthii, and O. punctata, combined with synonymous substitution rate tests and other evidence, we were able to identify potential recently duplicated genes, which evolved within the last 1 Myr. We identified 28 functional O. sativa genes, which likely originated after O. sativa diverged from O. glaberrima. These genes account for around 1% (28/3,176) of all annotated genes on O. sativa’s Chr3s. Among the 28 new genes, two recently duplicated segments contained eight genes. Fourteen of the 28 new genes consist of chimeric gene …