The Homeobox (Hox) gene promotes the development of muscle, bone, nerves, and anabolic hormones that are important for athletic success. Variations in this gene help determine muscle power, endurance, and visual/spatial skills. A way to predict if a person has the favorable version of the Hox gene is to measure the ratio of the length of the 2nd and 4th fingers (2D:4D). People with relatively longer 4th fingers (lower 2D:4D ratios) tend to be better athletes.
A Temple University study compared 2D:4D of 92 NCAA Division I athletes with 138 nonathletes. The ratio order (lowest to highest) among the subjects was football, gymnastics, soccer, nonathletes, and crew. While this is an interesting concept, we need more research to determine its validity as a predictor of athletic potential and its applicability in specific sports. (Journal Strength Conditioning Research 25: 1085-1088)