Diagnosis of 22q11 deletion and duplication in congenital heart disease by multiplex ligation dependent probe amplification / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To investigate the clinical utility of multiplex ligation-dependent probe amplification (MLPA) for detecting 22q11 deletion and duplication in congenital heart disease (CHD) cases and to study the incidence of 22q11 deletion and duplicaton in different kinds of CHD.</p><p><b>METHODS</b>Forty eight probes of which 25 located in 22q11 low copy number region (LCR 22s A-H), 7 in 22q11 surrounding region (CES, 22q13) and 16 in chromosomes 4, 8, 10 and 17 were selected to detect 22q11 deletion and duplication in 181 preoperative children with CHD and 14 fetuses with serious CHD or CHD with multiple malformations. In these cases, karyotype analysis was also performed.</p><p><b>RESULTS</b>MLPA demonstrated that 7 cases had 22q11 deletion [6 cases from CLTCL1 to LZTR1(LCR A-D) and 1 case from CLTCL1 to PCQAP (LCR A-C)] and that 1 case had 22q11 duplication,spanning from ZNF74 to LZTR1(LCR B-D). The phenotypes of heart defect included ventricular septal defect, atrioventricular septal defect, pulmonary stenosis and tetralogy of Fallot. Karyotype analysis showed that 1 case had 21q deletion [46, XY, 21q], 1 case had mosaic trisomy 8 [47,XY, +8/46, XY(1:2)] and 4 cases had trisomy 21. One of the 4 cases with trisomy 21 had concurrent 22q11 duplication.</p><p><b>CONCLUSIONS</b>MLPA is a rapid, sensitive, site specific and relatively inexpensive method for diagnosis of 22q11 deletion and duplication in CHD. 22q11 deletion and duplication may cause various kinds of CHD, suggesting that genetic detection should be performed routinely in CHD patients.</p>

Insulinllike growth factor 2 imprinting status and promoter usage in the placenta of macrosomia / 中华妇产科杂志

Objective To study the mechanism of marcosomia by investigating insulin-like growth factor 2(IGF_2)imprinting status,expression level and the promoter usage in the placenta of macrosomia. Methods We selected heterozygous cases for Apa Ⅰ polymorphism in exon 9 of IGF_2 gene and then analyzed its imprinting status in 168 placentas of macrosomia and normal pregnancies.IGF_2 transcription levels and promoter usages in macrosomic and normal placenta were evaluated by using semi-quantitative RT- PCR assay.Results Thirty specimens of macrosomic placenta and 30 of normal placenta were identified as heterozygous for IGF_2.All of the heterozygous specimens showed maintenance of imprinting.The expression of placental IGF_2 mRNA(2.2?1.2)was significantly higher in macrosomia than that of normal weight group (1.6?0.6,P 0.05).Conclusion It is possible that over expression of IGF_2 in placenta contributes to macrosomia while the promoter usage and imprinting status are not associated with macrosomia.