Mulligan L, Holden J J, White B N
Hum Genet. 1987 Apr;75(4):381-3. doi: 10.1007/BF00284113.
We have isolated a DNA segment, pX58dIIIc, from an X-chromosome library which identifies an SstI restriction fragment length polymorphism (RFLP) at locus DXS99. Linkage analysis in six informative families has shown that the DXS99 locus lies close to the factor IX gene (F9). No recombination was detected between these loci in 39 informative meioses (Z = 9.79, theta = 0.0). Therefore, DXS99 will be useful as a DNA marker for the assessment of carrier status in families with haemophilia B where intragenic markers are not informative. Heterozygosity at DXS99 is approximately 50% and, in conjunction with the RFLPs at F9, 90% of females at risk for being haemophilia B carriers should be diagnosed.
我们从一个X染色体文库中分离出了一个DNA片段pX58dIIIc，它可识别位于DXS99位点的SstI限制性片段长度多态性（RFLP）。在六个信息丰富的家系中进行的连锁分析表明，DXS99位点靠近凝血因子IX基因（F9）。在39次信息丰富的减数分裂中，未在这些位点之间检测到重组（Z = 9.79，θ = 0.0）。因此，对于乙型血友病家系中基因内标记无信息价值的情况，DXS99将作为一种DNA标记用于评估携带者状态。DXS99的杂合度约为50%，并且与F9处的RFLP结合，90%有乙型血友病携带者风险的女性应能得到诊断。
