PEG1 MEST IMPRINTED GENE ON CHROMOSOME-6 IDENTIFIED BY CDNA SUBTRACTION HYBRIDIZATION/

Parthenogenesis in the mouse is embryonic lethal partly because of imp rinted genes that are expressed only from the paternal genome, In a sy stematic screen using subtraction hybridization between cDNAs from nor mal and parthenogenetic embryos, we initially identified two apparentl y novel imprinted genes, Peg1 and Peg3, Peg1 (paternally expressed gen e 1) or Mest, the first imprinted gene found on the mouse chromosome 6 , may contribute to the lethality of parthenogenones and of embryos wi th a maternal duplication for the proximal chromosome 6, Peg1/Mest is widely expressed in mesodermal tissues and belongs to the alpha/beta h ydrolase fold family. A similar approach with androgenones can be used to identify imprinted genes that are expressed from the maternal geno me only.