Achalasia is a condition characterized by impaired function of esophageal motility and incomplete relaxation of the lower esophagus sphincter, causing dysphagia and regurgitation. Rare cases of early‐onset achalasia appear often in combination with further symptoms in a syndromic form as an inherited disease.

中文翻译：

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鼠逆转录病毒整合位点 1 基因的纯合突变与非综合征型的孤立性家族性贲门失弛缓症相关。

贲门失弛缓症是一种以食管运动功能受损和食管下括约肌松弛不完全为特征的疾病，导致吞咽困难和反流。罕见的早发性贲门失弛缓症通常与作为遗传性疾病的综合征形式的其他症状同时出现。