Objective To identify genes expressed in the fetal heart that are potentially important for myocardial development and cardiomyocyte proliferation.Methods mRNAs from fetal (29 weeks) and adult cardiomyocytes were use for suppression subtractive hybridization ( SSH) . Both forward (fetal as tester) and reverse ( adult as driver) subtractions were performed. Clones confirmed by dot-blot analysis to be differentially expressed were sequenced and analyzed.Results Differential expressions were detected for 39 out of 96 (41 %) clones on forward subtraction and 24 out of 80 (30%) clones on reverse. For fetal dominating genes, 28 clones matched to 10 known genes (COL1A2, COL3A1 , endomucin, HBG1 , HBG2, PCBP2, LOC51144, TGFBI, vinculin and PND), 9 clones to 5 cDNAs of unknown functions (accession AK021715, AF085867, AB040948, AB051460 and AB051512) and 2 clones had homology to hEST sequences. For the reverse subtraction, all clones showed homology to mitochondrial transcripts.Conclusions We successfully applied Objective To identify genes expressed in the fetal heart that are potentially important for myocardial development and cardiomyocyte proliferation. Methods mRNAs from fetal (29 weeks) and adult cardiomyocytes were used for suppression subtractive hybridization (SSH). Both forward (fetal as tester) and reverse Clones confirmed by dot-blot analysis to be differentially expressed were sequenced and analyzed. Results of Differential expressions were detected for 39 out of 96 (41%) clones on forward subtraction and 24 out of 80 (30 % clones on reverse. For fetal dominating genes, 28 clones matched to 10 known genes (COL1A2, COL3A1, endomucin, HBG1, HBG2, PCBP2, LOC51144, TGFBI, vinculin and PND) AK021715, AF085867, AB040948, AB051460 and AB051512) and 2 clones had homology to hEST sequences. For the reverse subtraction, all clones showed homology to mitochondrial transcripts.Conclusions We su ccessfully applied