来自《耶鲁大学开放课程：生物医学工程探索 第5集 第5集》

• 
  
  Usually this is a disease
  通常在疾病是由
• 
  
  that's caused by a defect in a single gene.
  单基因缺陷引起时才可行
• 
  
  We talked about sickle cell anemia last time,
  上次我们讲过镰刀状贫血病
• 
  
  that's an example.
  那就是一例
• 
  
  Another example is cystic fibrosis.
  另一例是囊胞性纤维症
• 
  
  Cystic fibrosis is a disease that affects many organ systems,
  囊胞性纤维症可导致多个器官病变
• 
  
  but particularly the lung.
  但尤其是肺部
• 
  
  You get cystic fibrosis because one protein
  得囊胞性纤维症的病因是
• 
  
  that's made by your lung epithelium
  肺上皮细胞产生的一种蛋白
• 
  
  is not expressed properly.
  表达不正常
• 
  
  You're able to make the protein
  肺上皮细胞可以表达这种蛋白
• 
  
  but the protein doesn't function properly.
  但其并不具有正常功能