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Small supernumerary marker chromosomes (sSMC) are structurally abnormal chromosomes that cannot be identified or characterized unambiguously by conventional banding cytogenetics alone, and they are generally equal in size or smaller than a chromosome 20 of the same metaphase s ...

The most common aneuploidies in prenatal diagnostics of the second trimenon are trisomies of chromosomes 13, 18, and 21 and gonosomal abnormalities. To detect these trisomies as quickly as possible after amniocentesis, besides using polymerase chain reaction, fluorescence in situ h ...

Since its discovery by Koch in 1989, primed in situ labeling (PRINS) reaction provides an alternative approach for direct detection of human chromosomes. The multiple color (multi)-PRINS technique can simultaneously and specifically display different chromosomes with differ ...

Microarray-based comparative genomic hybridization (array CGH) is a fast and high-resolution approach to the diagnosis of a large number of genetic syndromes associated with loss or gain of the human genome. This technology has proven to be useful in several clinical settings, including ...

Autosomal chromosome aneuploid pregnancies that survive to term, namely, trisomies 13, 18, and 21, account for 89% of chromosome abnormalities with a severe phenotype. They are normally detected by full karyotype analysis of cultured cells. The average reporting time for a prenatal karyo ...

Multiplex ligation-dependent probe amplification (MLPA) is a new method to determine the copy number of up to 45 genomic DNA sequences in a single multiplex polymerase chain reaction (PCR)-based reaction. In contrast to standard multiplex PCR, only one pair of PCR primers is used. MLPA reacti ...

In prenatal analysis, one of the major concerns is the detection of fetal aneuploidies. Several molecular methods have been described recently for the rapid analysis of amniotic fluid and chorionic villi. Fluorescence in situ hybridization (FISH) and polymerase chain reaction (PCR) of ...

Rhesus D (RhD) blood group incompatibility between mother and fetus can occasionally result in maternal alloimmunization where the resultant anti-D can cross the placenta and attack the fetal red cells, which in worse case scenarios can cause fetal anemia and ultimately death. Fetal RHD ge ...

Matrix-associated laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry is a tool currently under investigation for use in prenatal detection of abnormalities in chromosome number, such as trisomy 21. Because of its ability to detect extremely small diffe ...

Cell-free fetal DNA present in the maternal circulation holds great potential for noninvasive prenatal diagnosis and analysis of fetal genetic traits. However, only approximately 3–6% of total DNA in the maternal plasma is of fetal origin. Because of its scarcity in the maternal circulati ...

For fetal DNA extraction, in principle each DNA extraction method can be used; however, because most methods have been optimized for genomic DNA from leucocytes, we describe here the methods that have been optimized for the extraction of fetal DNA from maternal plasma and validated for this purp ...

The analysis of cell-free fetal DNA in the circulation of the pregnant woman plays the pivotal role in noninvasive prenatal research. Here, we describe an improved method for the quantification of male DNA, which is a valuable research tool for the quantification of fetal DNA. The quantificati ...

Since the demonstration of cell-free fetal DNA in maternal circulation, its aberrational quantification has been explored and demonstrated in numerous clinical situations. Moreover, several centers have begun to use detection and quantification of fetal DNA to diagnose fetal ge ...

Recent studies have shown that cell-free fetal DNA in maternal plasma can be enriched by means of size fractionation. This technique makes use of the smaller size of fetal DNA fragments compared with maternal DNA fragments isolated simultaneously. On this basis, a highly improved detection of ...

The discovery of cell-free fetal DNA in the plasma and serum of pregnant women has opened a new window for noninvasive prenatal diagnosis. Robust detection and quantification have been achieved when the fetal DNA sequence of interest does not have a maternal counterpart (e.g., Y chromosomal DNA, ...

The discovery of cell-free RNA in plasma and serum samples provides possibilities for noninvasive prenatal diagnosis. Quantitative alterations of cell-free placental-derived mRNA in the maternal circulation are associated with many pregnancy-related disorders, such as pr ...

Circulating fetal RNA in maternal plasma has offered a new approach for noninvasive prenatal diagnosis and monitoring. Circulating fetal RNA markers could potentially be used for all pregnant women without being limited by fetal–maternal genetic polymorphisms and fetal gender. O ...

A novel in vitro method is described wherein gene expression profiling is reflective and informative for the way how syncytiotrophoblast cells shed RNA products in vivo in maternal plasma. After controlled denudation, RNA is obtained selectively from the syncytiotrophoblast cells ...

Circulating cell-free fetal deoxyribonucleic acids (cffDNAs) are promising biomarkers with various potential clinical applications. Second and third trimester amniotic fluid (AF) is a rich source of cffDNAs. Further improvements to the original protocol for the extraction of ...

Proteomics has brought with it the hope of identifying novel biomarkers for the fetal aneuploidies. This hope is built on the ability of proteomic technologies, such as two-dimensional gel electrophoresis (2-DE) with immobilized pH gradients combined with protein identification by ...