The TUBB2A gene provides information to produce a protein that is necessary for cell structure (the cytoskeleton), cell division and cellular movements. This beta-tubulin protein is part of a group of proteins referred to as microtubule proteins. During brain development, microtubules are essential to create a sufficient amount of nerve cells (neurons) by the division (proliferation) of progenitor cells into daughter cells. These daughter cells then need to migrate to their final location in the grey matter (cerebral cortex) and form connections, for example with other neurons.
Pathogenic variants (mutations) in the TUBB2A gene cause the protein to malfunction. One result of abnormal protein function is a decreased amount of neurons due to impaired cell division. This often presents as a small head , called microcephaly. Mutations also cause disturbed neuronal migration to the grey matter, which leads to abnormal folds and grooves at the brain surface, referred to as dysgyria.
To date, all individuals with pathogenic variants in TUBB2A occurred de novo, meaning that they were not inherited by the parents. The mutation usually occurred spontaneously during early prenatal development.
TUBB2A