1病例介绍患者男,14岁,因视力下降10年余入院。患儿自幼饭量大,肥胖,六指及六趾,10岁时行双侧六指截除术;3岁时发现眼球震颤,夜间视物不清,手指及脚趾粗短,稍活动后即气喘,夜间呼吸困难。入学后学习成绩差,智力低下。患儿父母体健,有一哥二弟,其哥哥有类似症状,二弟体健。体检: 1 case description Male patient, 14 years old, due to decreased visual acuity more than 10 years admitted to hospital. Childhood meals since childhood, obesity, six fingers and six toe, at the age of 10 at both sides of the six-finger amputation; 3 years old found nystagmus, blurred vision at night, fingers and toes stubby, a little activity after asthma, Difficulty breathing at night. Poor academic performance after admission, mental retardation. Children with parents healthy body, a brother brother, his brother had similar symptoms, second brother physical health. Physical examination: