We validated analytical performance of droplet digital polymerase chain reaction (ddPCR) for detection of copy number variation of SMN1 and SMN2 genes for diagnosis of SMA using clinical samples.  For accuracy performance evaluation, ddPCR results were compared with those of multiplex ligation-dependent probe amplification (MLPA) as a reference standard.  Copy numbers of SMN1/SMN2 exon 7 from 200 clinical samples were concordant between ddPCR and MLPA.


 For all samples, the copy number of SMN1/SMN2 exon 7 was concordant between MLPA and ddPCR.  The ddPCR also showed acceptable degrees of repeatability and total imprecision.


 Therefore, ddPCR is expected to be useful for SMA diagnosis and to predict phenotypic severity of SMA patients by determining the copy number of SMN2 in clinical laboratories.
ddPCR
We validated analytical performance of droplet digital polymerase chain reaction (ddPCR) for detection of copy number variation of SMN1 and SMN2 genes for diagnosis of SMA using clinical samples.  For accuracy performance evaluation, ddPCR results were compared with those of multiplex ligation-dependent probe amplification (MLPA) as a reference standard.  Copy numbers of SMN1/SMN2 exon 7 from 200 clinical samples were concordant between ddPCR and MLPA.


 For all samples, the copy number of SMN1/SMN2 exon 7 was concordant between MLPA and ddPCR.  The ddPCR also showed acceptable degrees of repeatability and total imprecision.


 Therefore, ddPCR is expected to be useful for SMA diagnosis and to predict phenotypic severity of SMA patients by determining the copy number of SMN2 in clinical laboratories.
ddPCR
For accuracy performance evaluation, ddPCR results were compared with those of multiplex ligation-dependent probe amplification (MLPA) as a reference standard.  Copy numbers of SMN1/SMN2 exon 7 from 200 clinical samples were concordant between ddPCR and MLPA.


 For all samples, the copy number of SMN1/SMN2 exon 7 was concordant between MLPA and ddPCR. 
MLPA