TUBB3 and microlissencephaly: These results strongly suggest that tubulin mutations should be systematically searched in a context of microlissencephaly with corpus callosum agenesis, particularly when sporadic, starting in order of frequency by TUBA1A mutation screening, then TUBB2 and TUBB3. Based on literature review, some previously reported “severe LCH” fall in fact into the microlissencephaly group.