Heritability and Familiality of Temperament and Character Dimensions in Korean Families with Schizophrenic Linkage Disequilibrium

Objective

Categorical syndromes such as schizophrenia may represent complexes of many continuous psychological structural phenotypes along several dimensions of personality development/degeneration. The present study investigated the heritability and familiality of personality dimensions in Korean families with schizophrenic linkage disequilibrium (LD).

Methods

We recruited 179 probands (with schizophrenia) as well as, whenever possible, their parents and siblings. We used the Temperament and Character Inventory (TCI) to measure personality and symptomatic dimensions. The heritability of personality dimensions in a total of 472 family members was estimated using Sequential Oligogenic Linkage Analysis Routines (SOLAR). To measure familiality, we compared the personality dimensions of family members with those of 336 healthy unrelated controls using analysis of variance (ANOVA) analysis.

Results

Three of the seven TCI variables were significantly heritable and were included in subsequent analyses. The three groups (control, unaffected first-degree relative, case) were found to significantly differ from one another, with the expected order of average group scores, for all heritable dimensions.

Conclusion

Despite several study limitations with respect to family recruitment and phenotyping, our results show that aberrations in several personality dimensions related to genetic-environment coactions or interactions may underlie the complexity of the schizophrenic syndrome.

[Alteration of cardiac beta-adrenoceptors and subtypes with increasing age]

The alteration of cardiac beta-adrenoceptor (beta-AR) and subtypes in Wistar rats of 48 and 10 weeks old were investigated by radioligand binding assay and functional determination of isolated perfused left atria. The results indicated that: (1) The density of cardiac total beta-AR was downregulated about 28% in 48 weeks old rats as compared with rats of 10 weeks old for both beta 1- and beta 2-AR; (2) The sensitivity of beta-AR and subtypes to isoproterenol in isolated perfused atria was significantly lowered in rats of 48 weeks old; (3) The beta-AR mediated contractile effect of 10 weeks old rat hearts was mainly attributed to beta 1 type, but equally to both beta 1 and beta 2 types in 48 weeks old rat hearts; (4) The two receptor subtypes showed mutually potentiation effect in 10 weeks old rat hearts when stimulated simultaneously, but only additive in 48 weeks old rat hearts.