| Background and ObjectiveThe morbidity of newbornbaby birth defect in our county is 4%-6%, that means there are increasing 100 ten thousands newborn babies, who have the birth defects every year in our country. Birth defects include the congenital abnormality, congenital hereditary disease and so on. The chromosome abnormality is the major reason of the birth defect newborn babies, and their common features are low intellectual function and abnormal development. Prenatal diagnosis can have a knowledge of the fetus development in the mother's uteri with various kinds of advanced science and technology, if we find the fetus that have the congenital abnormality or the deadly congenital hereditary disease and so on, we can create conditions for the intrauterine treatment and selective abortion.21,18,13,X and Y, these five chromosomal aneuploidies diseases take up more than 95% in all the newborn baby who are born with the birth defects. Detection these five chromosomal aneuploidies diseases is benefit of reducing the incidence of newborn baby birth defect, and realizing as the prenatal and postnatal care, and improving physical fitness among population. For a long time conventional chromosome cytogenesis analysis is recognized the Golden Standard of the chromosome disease. Though the method of karyotype analysis has the advantage of accurate and meticulous, it is waste time and energy, usually the result needs at least two weeks came out. The success ratio is 95%. These reasons imposed restrictions on the development of antenatal diagnosis in some extent. So we are pressed for a fast, accurate, simple and credible method of prenatal diagnosis.In the research, we compared fluorescence in situ hybridization with conventional chromosome cytogenetic analysis to evaluate the consistency of the two methods in the prenatal diagnosis of aneuploidy, and to evaluate whether the FISH have advantages of fast, effective and stable in the aneuploid prenatal diagnosis, and to discuss the clinical value application and feasibility.Materials and MethodsIn the study, we collected 200 cases, which was accord with prenatal diagnosis indications, enquiring to do amniotic fluid puncture and the gestational age was 16 weeks to 24 weeks, from July 2009 to December 2010 in the prenatal diagnosis center of the first affiliated hospital of Zhengzhou university. We discarded the first 2ml amniotic fluid, and then got 25ml amniotic fluid by B ultrasonic guided to do amniotic fluid puncture.5ml amniotic fluid was analysis by fluorescence in situ hybridization (FISH) technique. We chose the chromosome loci specificity (GLP) 13/21 double-color probe and the chromosome Centro mere probe CSP18/X/Y tricolor probe who were made by Beijing jin pu jia medical technology companies and they separately marked the 13,21,18,X,Y five kinds of chromosomes, and then we could detect the five common chromosome aneuploidy disease. Another 20ml amniotic fluid was analysis by traditional cell culture and karyotype analysis technique. And in the study period these two experiments were independent completed by two different groups until the end of the experiments; we announced the results and compared results of two methods.Result1. Amniotic fluid cell culture and karyotype analysis results199 case amniotic fluids cultured successfully and got the chromosome karyotype at the first time. There were totally detected 100 cases of 46,XX,94 cases of 46,XY, and five abnormal karyotype:one case of 45,XY,rob(13;14), one case of 47,XXY, one case of 47,XX,+21 and two cases of 47,XY,+21.1 case failed at the first time. The failed case:the pregnant woman was 25 years old, and had a tang screen high-screen, whose gestational age was 20 weeks; the amniotic fluid was turbid, at the first time cultured there was no cells cloned, and at the second amniotic fluid punctured there was a success, and the karyotype was 46,XY.2. The experimental of fluorescence in situ hybridization199 cases of amniotic fluid had a successful hybridization in 24-48h at one time, the results were consistent with the karyotype analysis results.â‘ we have detected one 47, XXY abnormal karyotype. When we used the FISH CSP18/X/Y tricolor probe to hybridization, these displayed two sky-blue signals (expressing two 18 chromosomes),2 green signal (say 2 X chromosomes), and a red signal (signify one Y chromosome) in the fluorescence microscopy.â‘¡And there have been detected three Down syndrome abnormal karyotype cases. When we used the FISH GLP13/21 double-color probe to hybridization, it showed 2 green signal (say two 13 chromosomes),3 red signals (represent three 21 chromosomes).â‘¢One failed case, at the first time of the amniotic fluid cell cultured, FISH had a successfully detection and it was a normal male fetus, which excluding tang high-risk screening.â‘£One case was 45, XY, rob (13:14), FISH have not been detected, FISH detected as a normal male fetus, and it is a false negative result.3. Compared the FISH results with the karyotype'sFISH had a higher success rate compred with the karyotype analysis. FISH had high consistency with the karyotype analysis for the detection of the common chromosom aneuploidy in prenatal diagnosis, and the sensitivity was (4/4) 100%, the specificity was (195/195) 100%; for the detection of chromosomal abnormality karyotype the sensitivity was (4/5) 80%, specificity was (195/195) 100%.Conclusion1. FISH detected the most common five chromosomal aneuploidy abnormalities:it is consistent with karyotype analysis, and can be fast, stable and effective to detection chromosome aneuploid fetal anomalies, and have a great significance to establish a fast, stable and effective fetal aneuploidy prenatal diagnosis. It had a high clinical value and feasibility.2. FISH couldn't detect the chromosomal aneuploidy abnormalities which arn't marked by the fluorescence and the complex chromosomal of structural abnormalities such as the balance shifts and so. |
PDF Full Text Request