developmental stages. For example, in the frontal cortex of the embryonic stage, the top 10% of connected genes were enriched with biological processes critical for cell cycle, cell differentiation, and cell growth in the embryonic stage (Fig. 6). Synaptic transmission and catabolic process, however, were enriched for the most connected genes in the frontal cortex of the adolescence stage (Fig. 7). Similar enriched functional clusters were observed in other brain regions of the two stages (Additional file 11). These results strongly suggest that different genes in the 22q11.2 region play important temporospatial roles in different periods of brain development and haploinsufficiency of 22q11.2 genes have distinct functional impacts in different brain regions during brain development. This is also manifested at least partially by the temporal expression profiles of the 22q11.2 genes in brain regions at different developmental stages (Additional file 12).
