Development of a Multiplex Selected Reaction Monitoring Assay for Quantification of Biochemical Markers of Down Syndrome in Amniotic Fluid Samples

Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada.
Journal of Proteome Research (Impact Factor: 4.25). 06/2012; 11(7):3880-7. DOI: 10.1021/pr300355a
Source: PubMed


Down syndrome (DS) is one of the most common chromosomal abnormalities affecting about 1 of every 700 fetuses. Current screening strategies have detection rates of 90-95% at a 5% false positive rate. The aim of this study was to discover new biomarkers of DS in amniotic fluid by using a multiplex selected reaction monitoring assay. Nine proteins were analyzed: CEL, CPA1, MUC13, CLCA1, MUC5AC, PLUNC, and HAPLN1, and CGB as positive control and serotransferrin as negative control. One proteotypic peptide for each protein was selected, and internal heavy isotope-labeled peptide standards were spiked into the samples. Fifty-four samples from pregnant women carrying normal (n = 37) or DS-affected (n = 17) fetuses were analyzed. The median protein concentrations for DS and normal samples, respectively, were as follows: 20 and 49 ng/mL (p < 0.01) for CEL; 3.7 and 14 ng/mL (p < 0.001) for CPA1; 80 and 263 ng/mL (p < 0.001) for MUC13; 46 and 135 ng/mL (p < 0.001) for CLCA1; 0.65 and 0.93 μg/mL (p < 0.05) for MUC5AC; 61 and 73 ng/mL (p > 0.05) for PLUNC; 144 and 86 ng/mL (p < 0.01) for HAPLN1; 0.89 and 0.54 μg/mL (p = 0.05) for CGB; 91 and 87 μg/mL (p > 0.05) for serotransferrin. Statistically significant differences were found in six out of the seven candidate proteins analyzed, reflecting a different regulation in DS.

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Available from: Eduardo Martínez-Morillo, Dec 15, 2014
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    • "Likewise, extensive analysis of the amniotic fluid proteome was completed in order to identify biomarkers for diagnosis of Down syndrome and fetal diseases [58]. More than a thousand proteins were identified in the amniotic fluid of pregnant women carrying chromosomally normal fetuses and fetuses with Down syndrome at different gestational ages, and the most promising candidates were verified [52] [59] [60]. Since each type of biological sample has its own advantages and disadvantages , combination of complementary samples increases the likelihood to discover true positive markers. "
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