Figure 8: Direct mutation screening. Genomic DNA from patients and normal control are amplified for factor 8 or factor 9 gene coding and flanking intronic regions by a PCR. These amplicons are either screened by mutation screening methods to identify the PCR fragments that display heteroduplexes and sequenced to confirm the nature of nucleotide change. Alternatively, whole gene sequencing on all the PCR amplicons can be performed to identify the mutation.