Another ADHD candidate gene found in a large family by linkage analysis and replicated in parallel in a global case-control study (n = 2627 ADHD subjects, n = 2531 controls) is adhesion-G protein-coupled-receptor-L3 (ADGRL3, formerly LPHN3), a brain-specific G protein-coupled receptor with cell adhesion function [23]. Here, ADGRL3 is linked to attention deficit-hyperactivity disorder.