ZNRF3 and microcephaly: Here, we demonstrate such opposing effects on human brain size by distinct missense variants in the gene zinc RING finger 3 (ZNRF3 [MIM: 612062]) and show that an increase in Wnt/β-catenin signaling, in contrast to the aforementioned study,3 leads to macrocephaly, while a decrease in Wnt/β-catenin signaling leads to microcephaly.