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目的 探讨先天性髋关节脱位 (CDH) 与22、7号染色体之间的连锁关系.方法 以4个云南地区CDH家系为研究对象,提取所有家系成员的DNA.选用人类连锁协作中心 (CHLC) 开发的微卫星多态标记,其中8个平均分布于22号染色体,10个分布于7号染色体.进行PCR扩增,产物进行非变性凝胶电泳,银染色.凝胶分析系统行等位基因分型.应用Linkage软件包在不同的重组率条件下行参数型连锁分析,设疾病基因频率为0.02.结果 所有位点表现了较高杂合度和多态性,基因型数据符合孟德尔定律.22、7号染色体两点连锁分析,LOD值<1,表示不存在连锁关系.提示4个家系CDH与各微卫星位点不存在连锁关系.结论 排除云南地区CDH家系致病基因位于22、7号染色体上.“,”Objective To investigate genetic linkage between the phenotype of congenital dislocation of the hip (CDH) and genes located in chromosome 22,7, and attempt initially process of the genome-wide scan for searching disease-susceptibility loci.Methods According to epidemiological data,we studied 4 kindred with CDH in yunna,which include 65 persons in 5 generations.the affected status of 17 individuals had been established on the basis of their clinical and radiological presentation of the disorder.44 blood specimens were collected from those members who could be followed trail, and their nucleus DNA was extracted from peripheral leukocytes as phenol method.35 Tetnuc or Trinuc repeat microsatellite markers exploited by CHLC were chosen.8 markers distributed on chromosome 22, and 10 markers distributed on 7chromosome with an average interval of 10 cm.Genimic DNA were amplified by PCR technique.The PCR products were subjected to vertical electrophoresis in PAGE gel with continous buffer system, followed by siliver staining.graphic analysis system was used to define each allele.Parametric linkage analysi using maximum likelihood estimation were computed by the linkage package for various recombination fraction valus, with a disease gene grequency of 0.02.Results 18 STR loci are showen to provide good discrimination power by highly polymorphism and heterozygosity.Gnotype dated were obtained and conformed to Mendel law.Linkage analysis with those markers gave minus two-point LOD score values (Z<1), which the markers in 22and 7 chromosome indicated that there no linkage between the markers and CDH gene in those pedigrees.Conclusions CDH susceptibility genes are not likely located on chromosome 22, 7.The approach to geno-wide scan using highly density STR markers would play an important role in map the gene responsible for CDH.