A 27-bp deletion is responsible for the expression of a variant CABP1, a cyclic AMP-binding protein of Dictyostelium discoideum.

The two subunits of the cAMP-binding protein CABP1 in V12M2 differ in size from their counterparts in strain AX2. Sequence analysis shows that the CABP1 gene of V12M2 is missing 27 bp. Results from transfecting experiments provide further evidence that both subunits of CABP1 are encoded by the same gene.