TI - Results Transgenic myrAKT Lines . AB - We generated several AKT -activated transgenic lines as previously described [27] . The different lines present variability in both , the levels of expression of activated AKT and the degree of chimaerism , number of cells per duct expressing the transgene . Out of 7 expressing transgenic lines we selected 3 of them , EA5 , EA2 and EA4 that showed different levels of AKT activation ( measured as AKT PHOSphorylation at Ser473 ) ( Figure 1 ) . We quantified the value of AKT activation and observed that EA5 line showed low AKT activation , just above the basal levels , however , EA2 and EA4 showed atleast 5-7 fold activation . Due to chimaerism observed in most transgenic lines at difference from knock-ins models , the ducts also expressed variable percentage of cells expressing the transgene ( Figure 1A and D ) . While EA5 showed low number of cells with the transgene , EA2 and EA4 presented an average of 60% cells per duct with AKT activated ( Figure 1A ) . We did also generate the homozygous transgenic lines expressing two alleles of activated AKT . AKT levels increase in such homozygous lines (Fig 1C) although they do not double the levels of AKT activation . Similarly , homozygous lines increased the number of cells per duct expressing the transgene (Figure 1A) . Since MMTV is activated by hormones it is known that multiparous animals increased the levels of expression of the transgenes driven by such promoter . Therefore , we maintained both one colony of virgin and another colony of multiparous females . As expected , multiparous females expressed higher levels of activated AKT (Figure 1F) and a percentage of cells above 90% expressing the transgene (Figure 1D) . Therefore we can compare 12 different lines with different levels of AKT activation and a different percentage of cells per duct with transgene activation .