Exon/intron structure and alternative mRNA transcripts of mouse GAD1 gene. The new arrangement of mouse GAD1 exons and introns as determined after the analysis of genomic and cDNA sequence data using bioinformatics, 3′-RACE, RT-PCR, cloning and sequencing. Exons are shown as numbered boxes (red numbers represent alternatively spliced exons) and introns as lines. Large boxes indicate the coding DNA sequence and the small boxes the 5′- and 3′-untranslated regions. The red arrowheads are showing the locations of the alternative promoters. The schematic representation of GAD1 splicing isoforms in relation to the gene is shown below the gene structure. The length in base pairs and the position of start and stop codons are indicated above each isoform. Diagrams are not to scale.