  The widespread use of genetic testing in high risk pregnancies has created
strong interest in rapid and accurate molecular diagnostics for common
chromosomal aneuploidies. We show here that digital polymerase chain reaction
(dPCR) can be used for accurate measurement of trisomy 21 (Down's Syndrome),
the most common human aneuploidy. dPCR is generally applicable to any
aneuploidy, does not depend on allelic distribution or gender, and is able to
detect signals in the presence of mosaics or contaminating maternal DNA.
