Verification of a biomarker discovery approach for detection of Down syndrome in amniotic fluid via multiplex selected reaction monitoring (SRM) assay

► A multiplex SRM assay to analyze thirteen proteins in amniotic fluid was developed. ► SRM results correlated well with ELISA results for MMP2 protein. ► Bile salt-activated lipase, mucin-13, carboxypeptidase A1, dipeptidyl peptidase 4 and MMP2 were found differentially expressed in Down syndrome-affected amniotic fluid samples.