摘要目的 探讨单纯性圆锥动脉干畸形(CTD)染色体22q11.2微缺失发生率及临床表型分析.方法 应用多重连接探针扩增法(MLPA)对77例0～10岁单纯性CTD患儿进行染色体22q11.2微缺失筛查,并对阳性样本进行荧光原位杂交(FISH)验证.采用Fisher精度检验,P＜0.05有统计学意义.结果 用MLPA对77例单纯性CTD患儿进行了22号染色体微缺失筛查,其中55例法乐四联症(TOF),4例肺动脉闭锁伴室间隔缺损(PA-VSD),8例右室双出口(DORV),10例大动脉转位(TGA).6例(7.8%)患儿存在染色体22q 11.2微缺失,其中4例为TOF,1例为PA-VSD,1例为DORV;10例TGA患儿中均未发现22q11.2缺失.结论 单纯性CTD染色体22q 11.2微缺失发生率约为7.8%.单纯性CTD患儿中,PA-VSD,DORV及TOF比TGA更易发生染色体22q11.2微缺失.应加强对单纯性CTD患儿的遗传筛查及咨询.

abstractsObjective Congenital conotruncal heart defects were commonly found in DiGeorge (DGS) and velocardiofacial (VCFS) syndromes. The deletion of chromosome 22q 11.2 (del22q) has been demonstrated in sporadic or familial cases of conotruncal heart defect (CTD). The aim of this study was to investigate the frequency of del22q and clinical phenotypic analysis in patients with nonsyndromic CTD at a pediatric thoracic and cardiovascular surgical centre. Methods Seventy-seven non-syndromic CTD children (42 male, 35 female, aged 0-10 years) were recruited. History, physical examination and medical records were reviewed. Venous blood was collected for genomic DNA after informed consent. Chromosome 22q 11.2 microdeletion was screened with Multiplex Ligation-dependent Probe Amplification (MLPA) and Fluorescence in situ hybridization (FISH). Genotype phenotype correlations were performed using Fishers exact test. P values less than 0.05 on a 2-tailed test were considered significant. Results We examined 77 non-syndromic CTD patients for a 22q 11.2 deletion.55 patients presented with tetralogy of fallot (TOF), 4 with pulmonary atresia with ventricular septal defect (PA-VSD), 8 with double outlet right ventricle (DORV) and 10 with transposition of the great arteries (TGA). Six children (7.8%) were found to have a del22q; including four TOF, one DORV and one PA-VSD. Interestingly, none of the ten TGA children had the deletion. Conclusions Chromosome 22q 11.2 microdeletion is detected in 7.9% of children with non-syndromic CTD. There was a tendency of higher 22q11.2 microdeletion prevalence in those with PA-VSD, DORV and TOF. Molecular genetic screening of non-syndromic CTD children may be important for diagnosis and genetic counselling.