Psychologists from the University of Cambridge and Goldsmiths University say that, other things being equal, people who are of an open personality type are more likely to have musical ability than those who are not of an open personality type. Per the article:
In a study published this week in the Journal of Research in Personality, a team of psychologists identified that the personality trait 'Openness' predicts musical ability and sophistication....Psychologists from the University of Cambridge and Goldsmiths University teamed with the BBC to recruit over 7,000 volunteers, in what is the largest study to date on personality and musical expertise. The team led by doctoral researcher David Greenberg, tested the participants on various musical abilities including melodic memory and rhythm perception. Performance on these tests was then linked to their scores on the Big Five personality traits: Openness, Conscientiousness, Extraversion, Agreeableness, and Neuroticism (OCEAN). They found that aside from musical experience, the next best predictor of musical ability was personality, and specifically, Openness....Importantly, the researchers found that the links between personality and performance on the musical tasks were present even for people who indicated that they did not play a musical instrument. This means that there are individuals who have a potential for musical talent, but are entirely unaware of it....Those who want to find out how they score on their musical ability, preferences, and personality can take these tests at http://www.themusicquiz.org.
Hmm, I play cello, tuba, keyboards, and bass, although I'm rusty as hell.