AVPR1a and SLC6A4 gene polymorphisms are associated with creative dance performance

Abstract

Dancing, which is integrally related to music, likely has its origins close to the birth of Homo sapiens, and throughout our history, dancing has been universally practiced in all societies. We hypothesized that there are differences among individuals in aptitude, propensity, and need for dancing that may partially be based on differences in common genetic polymorphisms. Identifying such differences may lead to an understanding of the neurobiological basis of one of mankind's most universal and appealing behavioral traits--dancing. In the current study, 85 current performing dancers and their parents were genotyped for the serotonin transporter (SLC6A4: promoter region HTTLPR and intron 2 VNTR) and the arginine vasopressin receptor 1a (AVPR1a: promoter microsatellites RS1 and RS3). We also genotyped 91 competitive athletes and a group of nondancers/nonathletes (n = 872 subjects from 414 families). Dancers scored higher on the Tellegen Absorption Scale, a questionnaire that correlates positively with spirituality and altered states of consciousness, as well as the Reward Dependence factor in Cloninger's Tridimensional Personality Questionnaire, a measure of need for social contact and openness to communication. Highly significant differences in AVPR1a haplotype frequencies (RS1 and RS3), especially when conditional on both SLC6A4 polymorphisms (HTTLPR and VNTR), were observed between dancers and athletes using the UNPHASED program package (Cocaphase: likelihood ratio test [LRS] = 89.23, p = 0.000044). Similar results were obtained when dancers were compared to nondancers/nonathletes (Cocaphase: LRS = 92.76, p = 0.000024). These results were confirmed using a robust family-based test (Tdtphase: LRS = 46.64, p = 0.010). Association was also observed between Tellegen Absorption Scale scores and AVPR1a (Qtdtphase: global chi-square = 26.53, p = 0.047), SLC6A4 haplotypes (Qtdtphase: chi-square = 2.363, p = 0.018), and AVPR1a conditional on SCL6A4 (Tdtphase: LRS = 250.44, p = 0.011). Similarly, significant association was observed between Tridimensional Personality Questionnaire Reward Dependence scores and AVPR1a RS1 (chi-square = 20.16, p = 0.01). Two-locus analysis (RS1 and RS3 conditional on HTTLPR and VNTR) was highly significant (LRS = 162.95, p = 0.001). Promoter repeat regions in the AVPR1a gene have been robustly demonstrated to play a role in molding a range of social behaviors in many vertebrates and, more recently, in humans. Additionally, serotonergic neurotransmission in some human studies appears to mediate human religious and spiritual experiences. We therefore hypothesize that the association between AVPR1a and SLC6A4 reflects the social communication, courtship, and spiritual facets of the dancing phenotype rather than other aspects of this complex phenotype, such as sensorimotor integration.

Figure 1. Distribution of TAS in Female Dancers and Nondancers/Nonathletes

Figure 2. Distribution of TPQ Reward Dependence Scores in Female Dancers and Nondancers/Nonathletes

Figure 3. Epistatic Interaction between AVPR1a and SLC6A4 Contributes to the Creative Dance Phenotype

Promoter region polymorphisms in the AVPR1a receptor region possibly contribute to regional differences in brain arginine receptor 1a expression patterns [42]. Vasopressin release, and subsequent AVPR1a receptor activation, is partially regulated by serotonin (5-HT) [28]. 5-HT is removed from the synapse by the serotonin transporter (SLC6A4), which plays a major role in regulation of synaptic levels of this neurotransmitter. In turn, synaptic SLC6A4 mRNA and protein levels are controlled in part by the presence or absence of a promoter region 44-bp insertion/deletion [19]. Subjects with polymorphic variants of these two genes are therefore predicted to show differences in serotonergic and vasopressin tone that contribute to differences in higher psychological constructs including TPQ Reward Dependence (associated with AVPR1a and AVPR1a × SLC6A4 gene × gene interaction) and TAS (associated with SLC6A4 and AVPR1a × SLC6A4 gene × gene interaction). Dancers score high on these two personality constructs, suggesting the hypothesis that the association between AVPR1a and SLC6A4 polymorphisms and dancing is likely mediated by the action of these two genes primarily on social communication (measured by TPQ Reward Dependence scores) and spirituality (measured by TAS scores). Similar to genes contributing to other complex traits, there are no “dancing” genes but rather common polymorphisms that contribute to simpler endophenotypes [77], such as TPQ Reward Dependence and TAS, that constitute some of the critical psychological underpinnings of the dance phenotype.