Lesch et al. 2008). Of the 30 genes listed there, 8 genes (CTNNA2, MOBP, MAP1B, REEP5, ASTN2, ATP2C2, CDH13 and ITGAE) overlap with the list of the 80 top-ranked SNP findings, as indicated in Table 3. The authors highlight the findings for ASTN2, CSMD2, ITGA11, CTNNA2 and CDH13 in their discussion. All of these genes have earlier shown association with substance use disorders and related phenotypes, which is interesting in the light of the frequent comorbidity with such disorders in (adult) ADHD (44.1% in the current study). The five genes encode proteins involved in cell adhesion and/or cell–cell communication in development and maturation of the brain. Also the UNC5B (Table 3) and KALRN genes fit into this category. The latter encodes a protein present in the postsynaptic density which regulates dendritic spine development and is important for the neuronal plasticity underlying memory and learning (Lesch et al. 2008; Penzes and Jones 2008).Table 3Top 30 single SNPs located in gene regions (including 100 kb of flanking sequences) ranked according to the mean rank calculated across three statistics as reported by Lesch et al. (2008) for association with persistent ADHD in adultsSNPMean of ranksANOVA P valueLocusPhysical positionPositionGene functiona Additional remarksrs1124389715.63E-089q34.13134608104In intron of
