The research in the NeuroGeMM team is directed at understanding the neurobiology and the genetics of mammalian brain development in health and disease. The brain is frequently malformed in rare neurodevelopmental disorders and patients can present with intellectual disability, autism and epilepsy. How many genes influence brain development and what functional systems these genes operate in are important unsolved problems in developmental biology. To address this unmet need, we use innovative large-scale neuroanatomical phenotyping screens in transgenic mouse models. Our newly acquired high-resolution episcopic microscopy (HREM) technology is a block-facing serial sectioning imaging technique in which samples are embedded in resin and sectioned within the body of a fluorescence microscope using an automated microtome. HREM does not require the need of clearing or optical sectioning. The result is a multifluorescence 3D brain. Currently, 24 brain structures are routinely segmented by manual annotation.