fragile x syndrome造句

• The screnning and prenatal gene dignosis for fragile x syndrome using pfu dna
  综合征的筛查和产前基因诊断
• Fragile x syndrome ( fxs ) is the most common form of inherited mental retardation after down syndrome . it affects approximately 1 in 4000 males and 1 in 8000 females in the general population
  脆性x综合征( fragilexsyndrome ， fxs )是导致遗传性智力低下的主要原因之一，发病率仅次于先天愚型，在男性中的发病率约为1 / 4000 ，在女性中发病率约为1 / 8000 。
• To detect the patients and carriers of the fragile x syndrome , various analytic methods could be used . one is cytogenetic diagnosis to observe the expression of the fragile site fraxa located at xq27 . 3
  对脆x综合征的诊断，可以通过细胞遗传学方法观察分析x染色体相应脆性位点的表达情况，或是通过southern印迹杂交的方法直接分析cgg重复的扩增突变。
• The absence of the fmr1 gene product , fragile x mental retardation protein ( fmrp ) , is believed to be responsible for the typical physical and mental characteristics of the fragile x syndrome . alleles with between 43 and 200 cgg repeats are called permutation . they are generally unmethylated with normal transcript and protein level , but are extremely unstable during transmission to next generation
  带有前突变( n = 43 200 )的个体其fmr1基因通常不会甲基化，可以正常转录和翻译产生fmrp ，故没有临床表型出现，但是，在向下一代传递的过程中却是非常不稳定的，会从前突变扩增成为全突变。