TUBA1A and microcephaly: In particular, we define hard clinical endpoints and seminal features at disease onset and during the course of disease as well as distinctive characteristics: TUBA1A tubulinopathy is initially characterized by primary, progressive microcephaly and facial dysmorphisms including retrognathism and hypertelorism, developing facial diplegia and abnormalities of the muscular tone in the course of disease resulting in severe motor impairment.