Partial genomic sequence of the human ghrelin gene showing novel exon -1 and extended exon 0 transcription start sites. Exon sequences are boxed and in upper case letters. Extended exon 0 sequence is indicated by dashed boxes. Nucleotide positions are shown on the left and the translation initiation site of preproghrelin is indicated as +1. Intron boundaries are indicated by bold, and intron sequences by lower case letters. Five transcription start sites (TSS) determined by employing an OriGene human Sure-RACE panel, denoted TSS1-5, are underlined and indicated. TSS1 contains a 106 bp exon -1 (exon -1a) and splices into the complete, 736 bp 5' extended exon 0 (exon 0b) [GenBank:EF549561]. TSS2 [GenBank:EF549564] harbours a 92 bp exon -1 (exon -1b) and splices into a 197 bp exon 0 (exon 0c; exon acceptor site is indicated # and bold). TSS3-5 all initiate in exon 0 (exon 0 e-g, respectively). TSS3 was obtained from the ovary [GenBank:EF549563]; TSS4 from testis [GenBank:EF549562] and stomach; TSS5 from adipose tissue [GenBank:EF549565] and leukocytes.