  Generalized parton distributions with helicity flip are studied in the quark
sector, within a simple version of the MIT bag model, assuming an SU(6) wave
function for the proton target. In the framework under scrutiny it turns out
that only the generalized transversity distribution, H_T^q, is non vanishing.
For this quantity, the forward limit is properly recovered and numerical
results are found to underestimate recent lattice data for its first moment.
Positivity bounds recently proposed are fulfilled by the obtained distribution.
The relevance of the analysis for the planning of measurements of the quark
generalized transversity is addressed.
