The endophenotype concept of schizophrenia represents an important approach in the exploration of the neurobiology of the illness. An important characteristic of an endophenotype, that it can be found among the healthy, first-degree relatives of patients with schizophrenia.

We evaluated two systematic reviews of studies on two potential endophenotypes (theory of mind and informative morphogenetic variants) to confirm the possibility of them as biological and cognitive markers of the illness.

We planned to explore data from theory of mind and informative morphogenetic variant studies among the relatives of schizophrenia patients.

We evaluated two researches of studies published in PubMed, Medline,Web of Science and PsycINFO between the period of 1968 and 2014 (informative morphogenetic variants studies) and 1980 and 2014 (theory of mind studies).

11 studies on the appearence of informative morphogenetic variants in the relatives of schizophrenia patients were found with mixed results, while 15 studies and two meta-analyses were analysed on theory of mind studies among the first-degree relatives of patients with schizophrenia,the exploration of the latter studies showed also diverse findings.

Futher research is needed to clarify theory of mind and informative morphogentic variant alternations as endophenotypic markers of schizophrenia.

Acknowledgement: This study was supported by the National Brain Research Program Grant no. NAP KTIA NAP-A-II/12.