title: Toxoplasmosis-associated difference in intelligence and personality in men depends on their Rhesus blood group but not ABO blood group.
abstract: BACKGROUND
  The parasite Toxoplasma gondii influences the behaviour of infected animals and probably also personality of infected humans. Subjects with a Rhesus-positive blood group are protected against certain behavioural effects associated with Toxoplasma infection, including the deterioration of reaction times and personality factor shift.
  
  
  RESULTS
  Here, we searched for differences in the toxoplasmosis-associated effects between RhD-positive and RhD-negative subjects by testing 502 soldiers with two personality tests and two intelligence tests. The infected subjects expressed lower levels of all potentially pathognomic factors measured with the N-70 questionnaire and in neurasthenia measured with NEO-PI-R. The RhD-positive, Toxoplasma-infected subjects expressed lower while RhD-negative, Toxoplasma-infected subjects expressed higher intelligence than their Toxoplasma-free peers. The observed Toxoplasma-associated differences were always larger in RhD-negative than in RhD-positive subjects.
  
  
  CONCLUSIONS
  RhD phenotype plays an important role in the strength and direction of association between latent toxoplasmosis and not only psychomotor performance, but also personality and intelligence.
authors.affiliation: Department of Biology, Faculty of Science, Charles University in Prague, Prague, Czech Republic. flegr@cesnet.cz
authors.forename: Jaroslav
authors.initials: J
authors.lastname: Flegr
authors.forename: Marek
authors.initials: M
authors.lastname: Preiss
authors.forename: Jiří
authors.initials: J
authors.lastname: Klose
mesh_terms: D000017:ABO Blood-Group System; D006801:Humans; D007360:Intelligence; D008297:Male; D010551:Personality; D012204:Rh-Hr Blood-Group System; D011795:Surveys and Questionnaires; D014123:Toxoplasmosis / Q000523:psychology*
chemical_list: D000017:ABO Blood-Group System; D012204:Rh-Hr Blood-Group System