Solera J, Magallón M, Martin-Villar J, Coloma A
Unidades de Genética Molecular and Hemofilia, Hospital La Paz, Madrid, Spain.
Am J Hum Genet. 1992 Feb;50(2):434-7.
DNA from a patient with severe hemophilia B was evaluated by RFLP analysis, producing results which suggested the existence of a partial deletion within the factor IX gene. The deletion was further localized and characterized by PCR amplification and sequencing. The altered allele has a 4,442-bp deletion which removes both the donor splice site located at the 5' end of intron d and the two last coding nucleotides located at the 3' end of exon IV in the normal factor IX gene; this fragment has been replaced by a 47-bp sequence from the normal factor IX gene, although this fragment has been inserted in inverted orientation. Two homologous sequences have been discovered at the ends of the deleted DNA fragment.
通过限制性片段长度多态性（RFLP）分析对一名严重B型血友病患者的DNA进行了评估，结果表明在因子IX基因内存在部分缺失。通过聚合酶链反应（PCR）扩增和测序对该缺失进行了进一步定位和特征分析。改变后的等位基因有一个4442碱基对的缺失，该缺失移除了位于内含子d 5'端的供体剪接位点以及正常因子IX基因中外显子IV 3'端的最后两个编码核苷酸；这个片段已被正常因子IX基因的一个47碱基对序列所取代，尽管该片段是以反向插入的。在缺失的DNA片段末端发现了两个同源序列。
