应用生物素—链抗生物素蛋白系统的固相技术,对PCR扩增后DNA片段进行直接顺序分析,检测了东北地区13例经典型PKU患者PAH基因点突变.结果表明;13例PKU患者中检出7种点突变,发现7种PAH基因突变组合类型,其中突变R243Q、R413P、Y204C和R111X是分别位于PAH基因第7、12、6和3外显子处的4种常见突变.本研究准确可靠地确定了PAH基因分子缺陷的遗传机理,为该疾病的基因诊断和基因治疗提供了科学依据. The direct sequencing analysis of the DNA fragments amplified by PCR was performed using the solid-phase technique of the biotin-streptavidin system and the PAH gene point mutations in 13 classical PKU patients in northeastern China were detected.The results showed that in 13 PKU patients Seven kinds of point mutations were detected and seven types of PAH gene mutation combinations were found, among which the mutations R243Q, R413P, Y204C and R111X were the four common mutations located at exons 7, 12, 6 and 3 of PAH gene respectively. Accurate and reliable determination of the genetic mechanism of molecular defects in PAH gene provides a scientific basis for genetic diagnosis and gene therapy of the disease.