Abstract: TotM RNA was extracted from aborted—embryo of litchi ‘Guiwei’. Dephosphorylating RNA，removing the mRNA cap structure and ligating the RNA Oligo to decapped mRNA with GeneRacerTM Kit and then the first strand of cDNA was synthesized by reverse transcription． The 3’and 5’gene specific primers from differential expressing cDNA fragments( gene)，isolated from aborted-embryo of litchi varieties of Guiwei by SSH，was designed with Gene Tools．The full-length 3’and 5’ends of cDNA was amplified with the first cDNA as template and two gene specific primers or nested primers by PCR． Complete SAM gene sequence was obtained by BLAST comparison of the three fragments and splicing according to the overlapping regions． The sequence of the SAM synthetase gene is 1515 bp in length with an opening reading frame(ORF) encoding 393 amino acids．The nucleotide sequence exhibits about 79%—82% overall similarity to the corresponding gene of other organisms，and the amino acids is about 88%—91%． It was suggested that
the obtained cDNA was a SAM gene in aborted-embryo of litchi varieties of Guiwei.

Key words: Litchi, Aborted-embryo, S-adenosylmethionine synthetase gene(SAM gene)