Schizophrenia is highly familial neuropsychiatric disorder with heritability estimated at 60-90%. Even unaffected first-degree relatives of schizophrenia manifested some neuropsychological abnormalities as well as neurologic soft sign and morphologic anomalies. the aim of this study was to evaluate personality profile in first-degree relatives of schizophrenia compared to their schizophrenia probands and healthy controls and whether personality profile might be endophenotype of schizophrenia.

The subjects were 97 first-degree relatives of schizophrenia, 48 their schizophrenia probands, and 106 healthy controls, who completed Temperament and Character Inventory (TCI) scale. Relatives were further divided into presumed carriers and pesumed non-carriers by schizophrenia genetic loading. Group difference in TCI scores were compared by general linear model using age and gender as covariates.

1. 1. There were significant group differences in HA scores between healthy controls, relatives, and probands after controlling age and gender, in that HA scores were increased by healthy controls, relatives, and probands in order.

2. 2. Presumed carriers have higher HA scores than presumed non-carriers and healthy controls.

3. 3. Proband group showed significantly lower RD and lower P in temperament dimension and lower SD, lower C, and higher ST in character dimension compared to other groups.

We found that HA scores of first-degree relatives of schizophrenia is intermediate level between schizophrenia probands and healthy controls. Considering increase of HA with schizophrenia genetic loading, HA may be potential endophenotype of schizophrenia. Further research with longitudinal follow up is needed to elucidate the clinical implication of high HA observed in schizophrenia family.