%0 Journal Article %T Segmental Duplications as a Complement Strategy to Short Tandem Repeats in the Prenatal Diagnosis of Down Syndrome %J Iranian Journal of Medical Sciences %I Shiraz University of Medical Sciences %Z 0253-0716 %A Miri, Mohammad Reza %A Saberzadeh, Jamileh %A Behzad Behbahani, Abbas %A Tabei, Mohammad Bagher %A Alipour, Mohsen %A Fardaei, Majid %D 2019 %\ 05/01/2019 %V 44 %N 3 %P 214-219 %! Segmental Duplications as a Complement Strategy to Short Tandem Repeats in the Prenatal Diagnosis of Down Syndrome %K Multiplex polymerase chain reaction %K Microsatellite repeats %K Down syndrome %K Segmental duplications %R 10.30476/ijms.2019.44976 %X Background: Quantitative fluorescence-polymerase chain reaction (QF-PCR) is an inexpensive and accurate method for the prenatal diagnosis of aneuploidies that applies short tandem repeats (STRs) as a chromosome-specific marker. Despite its apparent advantages, QF-PCR is not applicable in all cases due to the presence of uninformative STRs. This study was carried out to investigate the efficiency of a method based on applying segmental duplications (SDs) in conjunction with STRs as an alternative to stand-alone STR-based QF-PCR for the diagnosis of Down syndrome. Methods: Fifty amniotic fluid samples from pregnant women carrying Down syndrome fetuses, 9 amniotic fluid samples with 1 or without any informative STR marker (inconclusive), and 100 normal samples were selected from Shiraz, Iran, between October 2015 and December 2016. Analysis was done using an in-house STR-SD-based multiplex QF-PCR and the results were compared. Statistical analysis was performed using MedCalc, version 14.Results: All the normal, Down syndrome, and inconclusive samples were accurately identified by the STR-SD-based multiplex QF-PCR, yielding 100% sensitivity and 100% specificity. Karyotype analysis confirmed all the cases with normal or trisomic results.Conclusion: The STR-SD-based multiplex QF-PCR correctly identified all the normal and trisomy 21 samples regardless of the absence of informative STR markers. The STR-SD-based multiplex QF-PCR is a feasible and particularly useful assay in populations with a high prevalence of homozygote STR markers. %U https://ijms.sums.ac.ir/article_44976_2ac4b23ce124469fa3c464ebd4a20dc0.pdf