目的 验证TBX1启动子区核苷酸变异与心脏圆锥动脉干畸形的相关性。方法 招募621 例心脏圆锥动脉干畸形患儿，采用MLPA方法检测患儿22q11.2 区基因组DNA的拷贝数，排除22q11.2 微缺失患儿。对605 例无22q11.2微缺失的心脏圆锥动脉干畸形患儿和588 例正常对照儿童，采用PCR扩增和基因测序方法，进行TBX1 启动子区序列分析(-2000..+1），并应用生物信息学软件对变异位点进行功能预测分析。结果 心脏圆锥动脉干畸形患儿中发现存在TBX1基因启动子区位点变异，其中包括3 个已报道的单核苷酸多态性（SNP）和7 个罕见变异位点，突变的发生率约为1.7%。应用AliBaba 2.1 对7 个罕见变异位点进行分析，显示其中3 个位点可能影响相关反式作用因子与TBX1 启动子区顺式作用元件的结合。结论 TBX1启动子区核苷酸变异可能与心脏圆锥动脉干畸形发生相关。

Objective To explore the correlation between mutations in the promoter region of TBX1 gene and conotruncal heart defects. Methods A total of 621 children with conotruncal heart defects were recruited. Multiplex ligation-dependent probe amplification (MLPA) was used to detect the copy numbers of chromosomal region 22q11.2. Children with 22q11.2 deletion were excluded. Polymerase chain reaction amplification (PCR) and gene sequencing were applied to analyze promoter region of TBX1 (-2000..+1) in 605 children with conotruncal heart defects without 22q11.2 deletion and 588 healthy children. Bioinformatics software was used to predict and analyze the function of the variable loci. Results There were mutations in the promoter region of TBX1 gene in children with conotruncal heart defects, including 3 single nucleotide polymorphisms (SNP) sites and 7 rare loci. The incidence of mutation was 1.7%. The analysis of 7 rare loci by AliBaba 2.1 to showed that 3 of them may influence the combination of trans-acting factors and cis-acting elements of the promoter of TBX1 gene. Conclusion The mutation in the TBX1 promoter region may be related to the occurrence of conotruncal heart defects.