To Detect And Study Chromosome22q11Microdeletion In Congenital Heart Disease

Objective：This experiment adopted fluorescence in situ hybridization (FISH) and multiplePCR methods to determine the relationship of Chromosome22q11microdeletion andCongential Heart disease and compare the advantages and disadvantages of thesetwo methods.Methods:We Selected200children with congenital heart disease as the case group and120healthy children as control group.Take their peripheral blood samples and do thefollowing experiment:1.Extracted the cells from the peripheral blood and made the appropriate concen-tration of liquid. Packed them in two EP tubes and labeled group A,group B;2. Group A samples:we adopted TUPLE1/ARSA DNA probe and combined withfluorescence in situ hybridization (FISH) to detect the microdeletion of22q11.3. Group B samples:we selected4polymorphic short tandem repeat makers(STR):22D₄₁,22D₄₂,22D₄₃, D22S873located in typical deletionregion(TDR) of chromosome22q11deletion and amplified them with PCR to verifythe FISH results.Results:1. The FISH results: Chromosome22q11microdeletion was detected in7/200patients with congential Heart disease, the frenquency of22q11deletion in patientswas3.5%(3/85) in VSD and6.3%(2/32) in TOF,7.6%(2,26) in VSD/ASD. no22q11deletion was detected in the rest patients with congential Heart disease and the controlgroup.2. The multiple PCR results: We detected8cases of Chromosome22q11microdeletion in200patients with congential Heart disease. one cases in childrenwith ventricular septal defect's result of the multiple PCR was positive,while its FISHresults were negative. 3. The evaluation result of PCR: sensitivity was100%; specificity was99.48%;false positive rate was0.52%; Kappa was0.929.4.The relationship between22q11microdeletion and congenital heart disease:Inthe case group,the proportion of22q11microdeletion was3.5%(7/200);In the controlgroup, the proportion of22q11microdeletion was0%(0/120). We analyzed theseresults with the Fisher's exact test. The result showed P=0.048(≤0.05).There weresignificant differences.5. The relationship between22q11microdeletion and the phenotype ofcongenital heart disease:(1)We divided the positive results into TOF(include TOFwith multiple malfarmations) groups,VSD groups,VSD/ASD guoups, and analyzedthem with Fisher's exact test. The result showed P=0.636(P＞0.05).There were nosignificant differences;(2)then we divided the complex CHD cases into TOF(includeTOF with multiple malfarmations) groups and the others.we analyzed them withFisher's exact test. The result showed P=0.608(P＞0.05).There were no significantdifferences (3)We also divided all patients (included case group and control group)into two groups(conotruncal defects group, non-conotruncal defectsgroup group). Theresult showed P=0.634(P＞0.05).There were no significant differences.Conculsion:1.Chromosome22q11microdeletion is correlation with Congential Heart disease.2.Chromosome22q11microdeletion is probably no correlation with the phenot-ypic of isolated Congential Heart disease.3.STR-based multiplex PCR can be used for screening of the22q11microdeletion...