Pappalysin-1, also known as pregnancy-associated plasma protein A, is a protein encoded by the PAPPA gene in humans. PAPPA is a secreted protease whose main substrate is insulin-like growth factor binding proteins. Pappalysin-1 is also used in screening tests for Down syndrome.
To assess the risk that the fetus a pregnant woman is carrying has a chromosome disorder such as Down syndrome (trisomy 21) or Edwards syndrome (trisomy 18).
The median PAPP-A MoM (multiples of the median in normal controls) in DS pregnancies was 0.30 (quartile range: 0.17-0.54).
