复拇合并三指节拇指畸形家系的基因分析研究

Gene analysis in one family with triphalangeal thumb and preaxial polydactyly

目的研究先天性复拇合并三指节拇指畸形的一个家系的临床表现及致病原因。方法在患者家系调查的基础上，应用聚合酶链反应（PCR）技术对极化活性区（zone of polarizing activlty，ZPA）调控序列进行扩增和测序分析。结果体检发现，患者存在单侧或双侧拇指的复拇合并三指节拇指畸形，部分患者还可合并轴前和轴后的多指畸形。病因研究提示，在所有患者ZPA调控序列的第105位碱基对上发现了C→G的点突变。结论复拇合并三指节拇指畸形家系患者由ZPA调控序列的第105位碱基对上C→G的点突变所致。

Objective To explore the clinical manifestation and gene mutation of one family with triphalangeal thumb and preaxial polydaetyly. Methods Based on the patient＇ s family investigation and clinical observation, the blood samples of the family members were taken and polymerase chain reaction （PCR） was used for DNA sequencing and analysis of the zone of polarizing activity （ZPA） regulatory sequence. Results Clinical observation showed that the patients suffered from bilateral or unilateral triphalangeal thumb and preaxial polydactyly. Some of them also had further preaxial and postaxial polydactyly. The gene analysis revealed a point C→G mutation at the 105 base pair within the ZPA regulatory sequence. Conclusion The congenital triphalangeal thumb and preaxial polydactyly in this Chinese family was caused by a point C→G mutation at the 105 base pair within the ZPA regulatory sequence.