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Fig. 4 | BMC Medical Genetics

Fig. 4

From: Development and validation of a high throughput, closed tube method for the determination of haemoglobin alpha gene (HBA1 and HBA2) numbers by gene ratio assay copy enumeration-PCR (GRACE-PCR)

Fig. 4

Normalization of GRACE-PCR assay to determine gene copy numbers. Raw melting curves show three distinct steps corresponding to the melting of the CLCN7, HBA1 and HBA2 gene products generated during the GRACE-PCR Screening Test (a). Setting the normalization regions N1 and N2 (dark grey bars) in the HRM analysis software allowed the gene copy number ratio for CLCN7:HBA1 to be determined (b). Re-setting the normalization regions to N3 and N4 (light grey bars) allowed the determination of the gene copy number ratio HBA1:HBA2 (c). The copy number for CLCN7 is assumed to be two, which allows the number of HBA1 copies to be calculated, which in turn allows the determination of the number of HBA2 copies

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