genetic typing methods of t. gondii strains have been extensively perfected in recent years. from a technical point of view, many tools usable for genetic studied on single-copy loci have been used: rflp, pcr-rflp, sequencing, rapd-pcr and isoenzyme analysis. we described the cloning and sequence analysis of the gene which encodes the major surface antigen (sag1 or p30) of t. gondii. sag1 is th...