Application of Fluorescence in Situ Hybridization Technique for The Screening of Prenatal Diagnosis

Background: In order to obstetric care of pregnancy in women with high-risk are suggested prenatal diagnosis through amni-otic fluid sampling for cytogenetic analysis of fetal cells. The purpose of this study was to assessing effectiveness of the rapid fluorescence in situ hybridization (FISH) technique for detect-ing Chromosomal numerical abnormalities (13, 18, 21, X and Y) in high-risk pregnancies.Materials and Methods: In this study a total of 136 samples were received for a FISH and/or a full karyotype for the screen-ing of prenatal diagnosis from high-risk pregnancies problem who were introduced to the Medical Genetic Laboratory of Dr. Keshavarz in Rasht between May, 2017 and May, 2019. In 97 samples both conventional culture techniques for getting karyo-type through G-banding techniques were applied in conjunction to FISH test, to compare the both the techniques carried out.Results: Among 97 patients, 81 normal for the five major chro-mosome abnormality and 12 patients were found to be abnor-mal (6 trisomy 21, 1 trisomy 13, 1 trisomy 18 and 4 monosomy X) and all the FISH results correlated with conventional cy-togenetics. A total of 136 patients for the chromosomal abnor-malities analyzed by both/or cytogenetics and FISH there were 114 (83.8%) normal, 12 (8.8%) cases were abnormal and an-other 6 (4.4%) cases were suspicious mosaic and 4 (3%) cases of culture failure. The detection rate of prenatal diagnosis with FISH in 97 patients was 95.8%. Based on the results of this study, there were no false-positive and false-negative autoso-mal or sex chromosomal results, within our established criteria for reporting FISH signals.Conclusion: Therefore FISH as a reliable and rapid method in prenatal screening method for detecting numerical chromo-somal abnormalities and has now been performed as a routine diagnostic procedure for detection of fetal aneuploidy.

Keywords:

Screening , Prenatal Diagnosis , Fluorescence in Situ Hybridization