A1BG and breast carcinoma: Isoform-specific RT-PCR in brain and liver of three mammalian species –human, rat and mouse- demonstrates co-expression of two GLS2 transcript variants showing alternative first exons (Figs. 1 and 2): a long GAB transcript, previously cloned from ZR-75 breast cancer cells [15], and a short LGA transcript, lacking the first exon of GAB, and first characterized in rat liver [13], [33].