Researchers believe they have found a link between the relative lengths of your index and ring fingers and a predisposition to the disease amyotrophic lateral sclerosis (ALS) 1. The disease is believed to be influenced by prenatal factors, although the precise aetiology is unknown. The relative lengths of your index and ring fingers (the 2D:4D ratio) indicate your level of exposure to prenatal testosterone. Hypothesising that high prenatal testosterone levels could be a factor in the development of ALS, the researchers tested this by examining the 2D:4D ratio of patients and their findings appear to support their theory. A quick internet search revealed that there are over 20 research papers published in 2011 so far on the 2D:4D ratio as an indication of various medical and psychological conditions. There are also sites which link the ratio to a number of less scientific theories such as ability in exams. So how reliable are these results, and can your fingers really indicate anything other than how long your fingers are? The GIST podcasters tackle this topic in their latest offering of GIST-y goodness.