Mouse models of human microdeletion/microduplication disorders such as DiGeorge [13] and Smith Magenis syndrome [14], also helped to detect expression changes at the mRNA and protein levels of genes integral to CNVs and identify the critical candidate genes for the phenotype (e.g. transcription factors Tbx1 for DiGeorge and RAI1 for Smith Magenis syndrome). The gene discussed is TBX1; the disease is Smith-Magenis syndrome.