ADAM 12 may be used to reduce the false positive rate of first trimester combined screening for Down syndrome

Prenat Diagn. 2010 Feb;30(2):110-4. doi: 10.1002/pd.2405.

Abstract

Background: ADAM12 has been shown to be an efficient maternal serum marker for Down syndrome (DS) in the first trimester; but recent studies, using a second generation assay, have not confirmed these findings. We examined the efficiency of a second generation assay for ADAM12.

Materials and methods: ADAM12 concentrations were determined in 28 first trimester DS and 503 control pregnancies using a novel Research Delfia ADAM12 kit. Log10MoM distributions of ADAM12 and correlations with other markers were established. Population performance of screening was estimated by Monte Carlo simulation.

Results: ADAM12 was significantly reduced in the first trimester in DS pregnancies with a log10MoM of -0.1621 (equivalent to 0.68 MoM) (p < 0.001). The reduction decreased with advancing gestational age. ADAM12 used with PAPP-A + hCG beta + NT (CUB screening) increased the detection rate (DR) from 86% to 89% for a false positive rate (FPR) of 5%. When used for a fixed DR of 90%, the addition of ADAM12 resulted in a 25% reduction of the FPR.

Conclusion: ADAM12 is a moderately effective DS marker. It is not a cost-effective addition to CUB screening, but may be used to reduce the FPR in selected high-risk cases.

Publication types

  • Comparative Study

MeSH terms

  • ADAM Proteins / blood*
  • ADAM12 Protein
  • Adult
  • Biomarkers
  • Case-Control Studies
  • Down Syndrome / blood*
  • Down Syndrome / diagnosis*
  • False Positive Reactions
  • Female
  • Humans
  • Mass Screening
  • Membrane Proteins / blood*
  • Pregnancy
  • Pregnancy Trimester, First
  • Prenatal Care

Substances

  • Biomarkers
  • Membrane Proteins
  • ADAM Proteins
  • ADAM12 Protein
  • ADAM12 protein, human