Cre recombination removes exons 1 through 3. Due to a cryptic splice site cre recombination of this allele produces a truncated transcript lacking the amino-terminal myristylation sequence, the CD4/CD8-interaction domain, and the epitope recognized by the 1F6 monoclonal antibody. This transcipt is generated from thymic transcipts that derive from the proximal promoter but not from the peripheral T cell transcripts deriving from the distal promoter. (J:152472)