Character Of Mongolian Horse Candidate Gene5-HT Receptor Partial Sequencing Of The PCR-SSCP Analysis

Serotonin (5-HT) and serotonin receptor (5-HTR) have been extensively studied in relation to both personality traits and behavior features in human and animals. It is identified that at least seven gene polymorphisms namely 5-HTR1(a,b,d,e,f), 5-HTR2(a,b,c), 5-HTR3, 5-HTR4, 5-HTR5(a,b), 5-HTR6 and 5-HTR7 exists in 5-HTR by molecular biology and pharmacology studies. In this study, we considered the association between the personality traits and the serotonin receptor (HTR1a, 1b, 2a and 2c family) gene polymorphisms in Mongolian horses.Sixty Mongolian horses (Age: 2-16 years old) were used for the questionnaire investigation about eight factor related to personal traits. As a result of the statistics evaluation of the questionnaire answers by the caretakers of those Mongolian horses, they were classed in two groups, namely, the friendly group (affable personality) which included 5 factors such as friendliness to people, cooperation, gentleness, patience and gregariousness and the unfriendly group (unaffable personality) which included 3 factors of curiosity, watchfulness and inflammability. On the other hand, the SNPs of HTR1a, 1b, 2a and 2c in the Mongolian horses were analyzed by the PCR-SSCP and by the direct sequencing of PCR products. And the association between the personality traits and the HTR-family genotypes in the Mongolian horses was examined statistically. The results of association were as follows.1. As for the SNP of A1316G sites in HTR1b gene, a high correlation was particularly recognized for the unfriendly group. In fact, though BB-type in HTR1b of the Mongolian horses was weakly related with the evident characteristic factors such as friendliness to people, cooperation, gentleness, patience and gregariousness, AB-type in HTR1b was related with the evident characteristic factors such as curiosity, watchfulness and inflammability strongly. It was suggested that the SNP of A1316G sites in HTR1b gene was strong relevance with personal traits in the Mongolia horses.2. Five kinds of AA, AB, BB, BC and CC genotypes were found in the SNPs of upstream region of HTR1a gene in the Mongolia horse. AB and CC genotypes showed comparatively high relevance in the factor of the friendliness to people than AA, BB and BC genotypes. In particular CC genotype in SNP of G735C of HTR1a gene related to the factor of watchfulness most highly.3. As for the downstream region of HTR1a gene, two kinds of SNPs of G1461A and T1472C was recognized in the Mongolian horse.And three kinds of AB, BB and BC genotypes were found in two SNPs. AB and BB genotypes showed clear relevance for the unfriendly group with 5 factors. However, BC genotype showed strong relevance in the unfriendly group with 5 factors. In particular BC genotype in SNPs of G1461A and T1472C of HTR1a gene related to the factor of curiosity most highly.