RESUMEN
Objective:To investigate the distribution characteristics of the abnormal karyotpye in Children of Chongqing, to provide the information for management, prenatal diagnosis and intervention. Methods:Samples of the peripheral blood lymphocyte from 4 628 children were prepared with routine cytogenetic methods,G-bangding was employed for karyotype analysis, and C-banding was used when necessary. Results:A total of 22.67%(1 049/4 628) patients were identified to have abnormalities with 73 kinds of karyotypes. Among these aberrations, 874(83.32%) cases were euchromosome malformation,159(15.16%)were sex chromosome malformation,and Down’s syndrome,Turner’s syndrome were the most common. Mental retardation,short stature and congenital malformation were the three main causes of genetic counseling,and the major age grades were infants,school children and preschool children in-sequence,42.57%(742/1 743)with mental retardation,9.98%(98/982) with short stature,and 8.10%(56/691)with congenital malformation were detected to have abnormalities,which were coincided with clinical diagnosis,respectively. Conclusion:The abnormal karyotypes are various and complex in Chongqing,routine karyotyping is necessary for children of mental retardation,congenital malformation and growth retardation with unknown reason,since it can benefit for early management and intervention of genetic diseases.