Essential genes are enriched among top-predicted germ cell genes. To produce the observed curve, genome-wide genes were sorted in descending order of predicted probability of being a germ cell gene. The fraction of essential genes was computed with an increment of 1,000 genes in the ranked sequence. To produce the random curve, genome-wide genes were randomized and the fraction of essential genes was computed with an increment of 1,000 genes. Randomization was repeated 100 times, and the average and standard deviation were displayed. A. Predictions from the spermatocyte model. B. Predictions from the oocyte model.