Investigation of Genetic Evidence for Sasang Constitution Types in South Korea

In Sasang constitutional medicine, both disease susceptibility and drug response are considered to be related to the characteristics of an individual's physiology and psychology: a theory which is central to traditional Korean medicine. Based on such observable characteristics, Sasang constitutional medicine classifies people into four constitutional types. Genetic studies of Sasang constitution would help reveal the inheritance patterns and models of the typological traits and, moreover, help with traditional medical diagnosis and treatment. To investigate the heritable aspect of Sasang constitution, we collected various pedigrees from South Korea. The study population has 101 pedigrees composed of 593 individuals. The determination of the Sasang constitution type of each individual was performed by doctors who diagnose the Sasang constitutional type of individuals as part of their professional practice. We calculated estimates of familial correlation and heritability. Parent-Offspring pairs showed the strongest familial correlation of Sasang constitutional type, with the correlation values of 0.21 and 0.28, followed by sibling pairs with the value ranging between 0.14 and 0.25. From the heritability analysis conducted with the Variance-Component method, the heritability of TE (Tae-Eum) type, SY (So-Yang) type, and SE (So-Eum) type were 55%, 41%, and 47%, respectively. This pattern of heritability was consistent with different set of analyses, which suggest the robustness of our result. Our result clearly shows that the Sasang constitution type is heritable, and further genetic analysis based on our result will shed light on the biological mechanism of Sasang constitution.

Intra-familial Correlations of Symptoms and Clinical Characteristics in Multiplex Korean Families with Schizophrenia / 신경정신의학

OBJECTIVES: This study aims at examining familial associations of symptoms and clinical characteristics in affected sibling or relative pairs of schizophrenia as an effort to identify genetically homogeneous phenotypes. METHODS: Forty-seven relative pairs with DSM-IV diagnosis of schizophrenia from thirty-five Korean families multiply affected with schizophrenia were ascertained. Direct interviews were done using the Korean version of Diagnostic Interview for Genetic Studies (DIGS). The Krawieka Rating Scale and the Schedule for the Deficit Syndrome were also applied for further evaluation of psychopathologies. Intra-familial concordances and correlations of clinical characteristics and symptoms were tested using chi-squared-test and Spearman's correlation. RESULTS: Significantly high concordance rate within relative pairs was found for the diagnosis of paranoid vs. non-paranoid subtype (chi-squared=7.623, p=0.006, df=1). Deficit vs. non-deficit syndrome also showed significant concordance (chi-squared=3.850, p= 0.0497, df=1). Among single symptom items in DIGS, only 'auditory hallucination' showed significant concordance rate (chi-squared= 5.503, p=0.019, df=1). Factor analysis for symptoms items in the Krawiecka Rating Scale indicated three symptom dimensions; negative, psychotic and affective. Psychotic (rho=0.442, p=0.003) and affective dimension scores (rho=0.427, p=0.004) showed significant intra-familial correlations. Age at onset of recognized psychotic symptoms showed significant correlation only within the male sibling pairs. CONCLUSION: Familial factors, possibly genetic factor contribute to the phenotypic characteristics of paranoid vs. non-paranoid subtype, deficit vs. non-deficit syndrome, auditory hallucination, and affective syndrome. It supports their use in the delineation of homogeneous subgroups for future genetic studies