KCNIP4 and attention deficit-hyperactivity disorder: In the first genome-wide association studies (GWAS) of ADHD performed by Neale et al., the top 25 single-nucleotide polymorphisms (SNPs) (based on P-value) implicated as interesting candidate genes included two genes encoding for voltage-gated potassium (Kv) channel-interacting protein 1 (KChIP1) and Kv channel-interacting protein 4 (KChIP4) [10].