一例嵌合型额外标记染色体患者崔英霞魏丽珠王咏梅蔡旺喜患者女，１５岁。因双手、足指趾关节、膝肘关节肿痛、变形，智力进行性减退５年就诊。患儿出生时正常，１岁以后易患病，智力正常，７岁上学。１９９１年以来，智力减退明显以致不能上学，并出现手、足指趾关节、膝... One case of chimerism additional marker chromosome patients Cui Yingxia Wei Li Zhu Wang Yongmei Cai Wangxi female patient, 15 years old. Due to hands, feet, toe joints, knee elbow swelling and pain, deformation, mental deterioration of 5-year treatment. Children born normal, 1-year-old susceptible to illness, mental retardation, 7-year-old school. Since 1991, the mental retardation is so obvious that he can not go to school and there are hands, feet, toe joints and knees.