The ring 14 syndrome is a rare condition caused by the rearrangement of one chromosome 14 into a ring‐like structure. The formation of the ring requires two breakpoints and loss of material from the short and long arms of the chromosome. Like many other chromosome syndromes, it is characterized by multiple congenital anomalies and developmental delays. Typical of the condition are retinal anomalies and drug‐resistant epilepsy. These latter manifestations are not found in individuals who are carriers of comparable 14q deletions without formation of a ring (linear deletions). To find an explanation for this apparent discrepancy and gain insight into the mechanisms leading to seizures, we reviewed and compared literature cases of both ring and linear deletion syndrome with respect to both their clinical manifestations and the role and function of potentially epileptogenic genes. Knowledge of the epilepsy‐related genes in chromosome 14 is an important premise for the search of new and effective drugs to combat seizures. Current clinical and molecular evidence is not sufficient to explain the known discrepancies between ring and linear deletions.

中文翻译：

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14 号染色体缺失、环和癫痫基因：一个包裹在谜团中的谜团

14 号环综合征是一种罕见的疾病，由一条 14 号染色体重排成环状结构引起。环的形成需要两个断点和染色体短臂和长臂的物质损失。像许多其他染色体综合征一样，它的特点是多种先天性异常和发育迟缓。典型的病症是视网膜异常和耐药性癫痫。在携带类似 14q 缺失但未形成环（线性缺失）的个体中未发现这些后一种表现。为了找到对这种明显差异的解释并深入了解导致癫痫发作的机制，我们回顾并比较了环状和线性缺失综合征的临床表现和潜在致癫痫基因的作用和功能的文献病例。了解 14 号染色体中的癫痫相关基因是寻找新的有效药物来对抗癫痫发作的重要前提。目前的临床和分子证据不足以解释环状和线性缺失之间的已知差异。