March Madness and time to follow your favorite U.S. college basketball teams during playoffs. Some of you may be baffled by how much mental energy, time, and money Americans invest in sporting events, but those who participate will expound on the excitement of watching spectacular athletes and the thrill of competition, or simply the fun of betting on the outcome. Investigating the different angles of March Madness turns out to be pretty interesting from a genetic perspective. First there is the genetics underlying athleticism, a trait that combines physical attributes like strength, coordination and stamina along with psychological behaviors – the ability to focus, to persevere and to compete. Then there is the genetics of the “spectator” who nearly becomes obsessed with basketball in these last two weeks of March. Genetic factors for the basketball player Being tall and getting across the court quickly might make you a better basketball player. Although height clearly has many contributing environmental factors, it also has a strong genetic component and researchers have found several inherited factors that contribute to height in people of European descent. For instance, those with at least one T at rs6060371 and one C at rs1042725 tended to be slightly taller on average. As for dashing across the court, research suggests that a SNP in the ACTN3 gene known as “R577X” (rs1815739) is linked to “fast-twitch” muscle fiber function. Fast-twitch muscle fibers are important for power events like sprinting and the C version of this SNP is carried by many world-class sprinters and some endurance athletes. Although it’s likely that there are additional genetic and environmental factors that influence whether you’ll become a basketball star, these are a few that might help you make that basket. Genetic factors for the spectator Unfortunately much less is known about why some people love watching basketball (or sports in general) and to our knowledge, scientists haven’t yet correlated genetic factors with this interesting behavior! It’s possible, however, that sex and environment are involved. One study showed that women are just as likely as men to report being sport fans, but men overall participate in more fan behavior. Women also seem to watch sports more if they do so with family and friends, though men follow sports because they themselves play and they enjoy the trivia aspect of following sports. So whether you are an aspiring basketball player, a passionate spectator, or simply enjoy watching curiously from afar, it’s clear that the genetics underlying March Madness is very complex. Perhaps with time researchers will sort out the role of genetics in these two very interesting arenas of athleticism and fan behavior.