Few, if any, genes have been associated with artistic creativity, and none, to our knowledge, specifically with dancing. The current study considered two genes, AVPR1a and SCL6A4, that are significantly associated with performing dancers. Although the association seems robust and is significant both by case-control and family-based designs, it is nevertheless a challenge to unravel the brain mechanisms by which these genes partially contribute to dancing, a phenotype extending across musical processing, motor coordination, and artistic creativity.
The association between AVPR1a
polymorphisms and creative dancing does not exclude the presence of the same polymorphisms in nondancing groups of subjects. Almost all of us dance and almost all of us have engaged in sports. What the current study suggests is that the combination of polymorphic variants contributing to creative dancing is overrepresented in the dancers. There is no reason to suggest that the nondancer athletes or the control group of nondancers/nonathletes are devoid of these polymorphisms, but the current study provides evidence that these variants are relatively scarce in other groups not specifically selected for the creative dancing phenotype. Importantly, we not only compared creative dancers to performing athletes but also validated the case-control design using a family-based study that avoids the conundrum of a comparison control group that might be “contaminated” with polymorphisms contributing to creative dancing. As for most complex traits, the effect size of these two genes is small and in Risch's terminology will have small displacement [41
gene makes a profound contribution to affiliative and social behavior in lower vertebrates [25
]. It is hypothesized that microsatellite promoter-region instability may be a major factor producing diversity in both region-specific gene expression and the resulting phenotypes [42
]. In humans, however, the role of the AVPR1a
repeat regions has yet to be resolved. Nevertheless, despite the dearth of research regarding the molecular mechanisms involved, the AVPR1a
promoter-region microsatellites have recently been associated with autism [23
], a disorder whose core symptom is a deficit in social communication. Additionally, we have shown that this gene is associated with measures of social behavior in control subjects [14
]. We suggest the notion that the association between AVPR1a
and dancing may be reflecting the importance of social relations and communication in the dance form and that both dance and its associated gene, AVPR1a,
contribute to molding social interactions from the molecular level to the dance floor. As noted by Kaeppler [1
], the cultural form produced in dance, although transient, has structured content and is a visual manifestation of social relations that may be the subject of an elaborate aesthetic system. It seems likely that one of the many prerequisites for a successful dance career is the capacity for social communication through dance (“embodiment”).
Intriguingly, Darwin recorded in The Voyage of the Beagle
(Chapter 19) his Australian encounter with the so-called White Cockatoo” aboriginal men and their performance in a corrobery,
or “great dancing-party.” As Darwin notes, “Perhaps these dances originally represented actions, such as wars and victories; there was one called the Emu dance, in which each man extended his arm in a bent manner, like the neck of that bird. In another dance, one man imitated the movements of a kangaroo grazing in the woods, whilst a second crawled up, and pretended to spear him” [43
]. It is worth noting in this context that the native Australians arrived on that continent approximately 50,000 y ago [44
]. Similarly, Native American, also known for their complex dance culture [1
], are estimated to have arrived in North America about 20,000 to 15,000 calendar years before the present [45
]. We conjecture that both groups arrived on their respective continents already with a dance culture (alternatively there was parallel “cultural” evolution of this art form) that we speculate is likely to have originated before the African exodus. The earliest evidence for dance is derived from a cave painting in Creswell, England, that depicts dancing women and is dated approximately 13,000 y ago [46
]. We hypothesize that this early evidence for dancing and its occurrence in groups geographically separated by thousands of years during our prehistory suggests a genetic basis for this behavior in H. sapiens.
Another aspect of dance is its spiritual side (e.g., sacred dancing across many diverse cultures) and the relationship of dance to altered states of consciousness; for example, in the Korean Salpuri dance, an ecstatic trance state is induced that results in changes in alpha wave activity [47
]. Dances in which the participant (often a woman) enters into a trance and may lose consciousness have been used in a therapeutic setting (e.g., to dispossess “demons”) in diverse cultures, including a North African Jewish community [48
]. We suggest the notion that the association we observe between SLC6A4
and dance is perhaps related to the need for altered consciousness states that subjects participating in and performing this art form sometimes have. Dancing may have its origins in shamanism, which sometimes used a potent and synergetic mix of music and dancing (and sometimes drugs) to alter consciousness [49
]. Perhaps a prerequisite for some types of dancing, in both sacred and more modern “profane” versions as either an artistic performer or a participant, is the ability to enter into such a higher state of awareness.
The personality construct of absorption is generally measured using the TAS, a self-report personality instrument with good psychometric properties [50
]. The TAS has been widely applied in research in an attempt to evaluate the significance of an individual's ability to attend intensely and imaginatively to stimuli. It has been found to correlate positively with spirituality and altered states of consciousness, such as an intrinsic religious orientation involving the internalization of religious tenets so they provide meaning and direction [51
], and the frequency and type of reported spontaneous mystical, visionary, and paranormal experiences [18
The short SLA6A4
promoter region polymorphism that we find associated with scores on the TAS characterizes a less efficient promoter, and in subjects carrying the short allele, less transporter protein is synthesized [19
], which would lead to altered synaptic levels of serotonin. It is not surprising therefore that we observe an association between TAS scores (indicating in some individuals a propensity to have mystical, visionary experiences, and/or “artistic” sensitivity) and a common genetic polymorphism that modulates synaptic serotonin levels. A large body of evidence links hallucinogens, drugs that alter consciousness, to serotonin, and it is thought that hallucinogens stimulate 5-HT2A
receptors, especially those expressed on neocortical pyramidal cells [57
]. Altered serotonin levels in carriers of the SLC6A4 promoter region allele might predispose such individuals to a greater ability for imagery and attention to stimuli (especially to musical stimuli) that we hypothesize may provide part of the “hard wiring” that talented and devoted individuals need to perform in an art form that combines a unique combination of both musical and physical skills.
Individuals high in TPQ Reward Dependence tend to be tender-hearted, loving and warm, sensitive, dedicated, dependent, and sociable [58
]. They seek social contact and are open to communication with other people. Typically, they find people they like everywhere they go and are sensitive to social cues, which facilitates warm social relations and understanding of others' feelings. The observed association between TPQ Reward Dependence scores and AVPR1a
is consistent with the role of the arginine vasopressin receptor in social communication as demonstrated in extensive animal experiments [59
]. The association between AVPR1a
and Reward Dependence personality traits strengthens the notion that this gene contributes to dancing through its contribution to social communication.
summarizes our notions of how polymorphisms in the AVPR1a and SLC6A4 genes contribute to the dance phenotype.
Epistatic Interaction between AVPR1a and SLC6A4 Contributes to the Creative Dance Phenotype
The proposed role of AVPR1a
in contributing to the dance phenotype in humans as provisionally shown in the current report has a solid evolutionary basis. Across the vertebrates, vasopressin plays a key role in courtship behavior that frequently involves elements of song and dance. For example, male zebra finches (Taeniopygia guttata)
sing directed song to females as an integral part of a courtship display that also includes elements of dance [60
]. The choreography of the dance presumably conveys or enhances some part of the message that is carried by the individual's learned song, although the exact importance and function of the dance are not known. Furthermore, arginine vasopressin plays a key role courtship behavior in zebra finches [61
] as well as in other bird species such as the territorial field sparrow (Spizella pusilla)
], as it does in social behaviors in mammals and other vertebrates [22
]. There is also evidence in humans that vasopressin is important in maternal and romantic love. Imaging studies have shown that brain areas rich in vasopressin receptors are activated when subjects are shown pictures designed to evoke feelings of attachment [63
]. The observation discussed above that AVPR1a
is associated with a temperament trait, Reward Dependence, also strengthens the conjectured role of this gene in human social communication. Thus, studies in humans as well as in many other animal species suggest to us the reasonable notion that variations in AVPR1a
microsatellite structure might also predispose some individuals to excel in dancing. Darwin observed that vocalization is a form of emotional expression, but among neuroethologists, questions concerning the role of emotion in vocal (and dance) communication have been superseded by questions that concern sensorimotor integration [64
]. We believe that the two genes we have identified with dancing in humans are likely involved in the emotional side of dance rather than in the sensorimotor mechanics of this complex phenotype. To quote West and King [65
], “Animals do not perceive or communicate for the sake of perceiving or producing a display, but for the sake of managing a social environment.” In this context, it is easier to see how the AVPR1a
receptor microsatellite polymorphisms contribute to human dance. Human dancing can be understood in part as a form of courtship and social communication that shares a surprisingly conserved evolutionary history, characterized by apparently common neurochemical and genetic mechanisms, with mating displays and affiliative behavior observed across the vertebrates.