Specific genotypes of arginine vasopressin receptor 1a (AVPR1a) and μ-opioid receptor (OPRM1) genes are related to social behavior in humans, chimpanzees, and rhesus monkeys. We surveyed these candidate genes in 77 captive common marmosets and found (GT)n polymorphism located in the intron of AVPR1a where 10 alleles were categorized as either being short (S: 202-210bp) or long (L: 212-222bp). We also found A111T (Leu37Phe) and T329C SNPs in OPRM1. Personality was assessed by ratings by three individuals familiar with each marmoset on the Hominoid Personality Questionnaire. Principal components analysis on 47 personality items yielded three domains labeled Dominance, Sociability, and Neuroticism. We conducted preliminary tests with unadjusted linear models to determine whether these personality domains were associated with AVPR1a or OPRM1 polymorphisms. For Sociability, marmosets possessing the SS genotype of AVPR1a were significantly higher than marmosets possessing the LL genotype. For Neuroticism, marmosets possessing the SL or SS AVPR1a genotype were significantly lower than marmosets possessing the LL genotype. Also in OPRM1 polymorphisms marmosets with the T/T genotype of both loci were higher and lower in Neuroticism, respectively. Finally we obtained cortisol hormone levels from hair samples and tested whether cortisol levels were related to genotype and/or personality. These findings, although preliminary, suggest that the same genes are responsible for personality variation across all three taxonomic families of primates.

The slow loris is listed as ‘Vulnerable’in the IUCN Red List because they are being overhunted for the illegal pet trade, used for meat and as ingredients of traditional medicine. In Vietnam, two species (Nycticebus bengalensis and N. pygmaeus) are found. The Center for Rescue and Conservation of Organisms (CRCO) of Hoang Lien National Park protects diverse organisms, including the slow loris, and tries to reintroduce them to the wild. However, it is hard to get information about the original habitat of confiscated animals. The purpose of the study is to accumulate mtDNA sequence data from slow loris of known origin, in order to establish a tracking system that infers the origin of these protected animals using DNA information. In this presentation, we report about the development of a mitochondrial marker that can detect intra-specific variation in these two species of slow loris. In order to avoid amplifying NUMT, we amplified the target region by using a long PCR product of the 9 kb region as template DNA. Next, we determined the target 1.8 kb region spanning a full length of cyt b gene and HVS1 of D-loop. Intra-specific variation was detected in both species, 9 N. bengalensis and 5 N. pygmaeus from Vietnam, including individuals without information of origin. Samples of N. bengalensis from Myanmar (n=2) and Laos (n=1) were included in the comparison of DNA sequence variations. The 1.8 kb region examined in this study can be applicable to the phylogeogaraphic study of the slow loris.