Simulation of the number of additional genotypes required for detecting selection on vkorc1 in the population from Hungary using the Fay and Wu normalized H statistic. Ref.  obtained synonymous variation for 3 of 12 rats available for that study. Ile82Ile was detected in 3/3 of those rats. The non-synonymous polymorphism at high frequency is Tyr139Cys, occurring in 10/12 rats. We simulate the number of additional rats with Ile82Ile that need to be identified in the nine remaining unanalyzed rats to yield significance for a selective sweep in this population. Significance levels 0.05 and 0.01 are indicated.