The FerI domain, but not the DysF domain, was discovered in ferlin-like proteins of protozoan Apicomplexan parasites Plasmodium (malaria), Theileria [Genbank:XP_765088] (East Coast fever), Babesia [Genbank:XP_001610088] (tick fever) and Toxoplasma [Genbank:XP_002364209] (toxoplasmosis) (data not shown), that account for significant worldwide mortality and morbidity amongst humans and livestock. This evidence concerns the gene DYSF and toxoplasmosis.