PURPOSE: To examine the potential high throughput capability and efficiency of 
an automated DNA extraction system in combination with mass spectrometry for the 
non-invasive determination of the foetal Rhesus D status.
METHODS: A total of 178 maternal plasma samples from RHD-negative pregnant women 
were examined, from which DNA was extracted using the automated Roche MagNA Pure 
system. Presence of the foetal RHD gene was detected by PCR for RHD exon 7 and 
subsequent analysis using the Sequenom MassArray mass spectrometric system.
RESULTS: We determined that as little as 15 pg of RHD-positive genomic DNA could 
be detected in a background of 585 pg of RHD-negative genomic DNA. The analysis 
of the clinical samples yielded a sensitivity and specificity of 96.1 and 96.1%, 
respectively.
CONCLUSION: Our study indicated that automated DNA extraction in combination 
with mass spectrometry permits the determination of foetal Rhesus D genotype 
with an accuracy comparable to the current approaches using real-time PCR.