The present invention provides methods for identifying polynucleotide and polypeptide sequences which may be associated with a commercially relevant trait in plants, specifically, so-identified polynucleotides and polypeptide sequences for yield-related genes EG9703 and EG8798 for rice, corn, wheat, barley, sorghum, and sugarcane. Sequences thus identified are useful in enhancing commercially desired traits in domesticated plants or wild ancestor plants, identifying related polynucleotide sequences, genotyping a plant, and marker assisted breeding. Sequences thus identified may also be used to generate heterologous DNA, transgenic plants, and transfected host cells.