Objective: To identify the genetic defect of a patient with clotting factor X deficiency (QGZ).
Methods: PCR and DNA sequencing were used to screen mutation in factor X gene. PCR primers were designed covering all the coding regions for exon and flanking intron sequences.
Result: A single nucleotide substitution T 58G in exon 1, which caused a missense mutation Ser(AGT) 11 Arg(AGG) in signal peptide, was identified by DNA sequencing.
Conclusion: This nucleotide substitution might be the molecular etiology of factor X deficiency.