During the past decade, there have been considerable advances in understanding of the genetic and morphogenic processes underlying cortical malformations and developmental brain tumours. Focal malformations are caused by somatic (postzygotic) variants in genes related to cell growth (ie, in the mTOR pathway in focal cortical dysplasia type 2), which are acquired in neuronal progenitors during neurodevelopment. In comparison, developmental brain tumours result from somatic variants in genes related to cell proliferation (eg, in the MAP-kinase pathway in ganglioglioma), which affect proliferating glioneuronal precursors. The timing of the genetic event and the specific gene involved during neurodevelopment will drive the nature and size of the lesion, whether it is a developmental malformation or a brain tumour. There is also emerging evidence that epigenetic processes underlie a molecular memory in epileptogenesis. This knowledge will together facilitate understanding of why and how patients with these lesions have epilepsy, and could form a basis for a move towards precision medicine for this challenging cohort of patients.

在过去的十年中，在了解皮质畸形和发育性脑肿瘤的遗传和形态发生过程方面取得了相当大的进展。局灶性畸形是由与细胞生长相关的基因（即，在 2 型局灶性皮质发育不良的 mTOR 通路中）中的体细胞（合子后）变异引起的，这些变异是在神经发育过程中在神经元祖细胞中获得的。相比之下，发育性脑肿瘤是由与细胞增殖相关的基因（例如，在神经节胶质瘤中的 MAP 激酶途径中）的体细胞变异引起的，这些变异会影响增殖的胶质神经元前体。遗传事件的时间和神经发育过程中涉及的特定基因将决定病变的性质和大小，无论是发育畸形还是脑肿瘤。还有新的证据表明，表观遗传过程是癫痫发生过程中分子记忆的基础。这些知识将共同促进对这些病变患者为何以及如何患有癫痫的理解，并可能为这一具有挑战性的患者群体转向精准医疗奠定基础。