• Turnaround time:
    10–21 calendar days (14 days on average)
  • Preferred specimen:
    3mL whole blood in a purple-top tube
  • Alternate specimens:
    DNA or saliva/assisted saliva
  • Sample requirements
  • Request a sample kit



F9 p22; FIX; HEMB; P19; PTC; THPH8

Associated disorders

The F9 gene is associated with X-linked recessive factor hemophilia B (MedGen UID: 945) and X-linked recessive factor IX thrombophilia (MedGen UID: 411730).

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Invitae tests that include this gene:

The F9 gene is the only known gene to cause X-linked recessive thrombophilia. The percentage of thrombosis attributed to pathogenic variants identified in F9 is unknown.

The F9 gene encodes the coagulation factor IX protein, which is activated by factor XI and in turn activates factor X during the coagulation pathway involved in stopping blood loss.

Assay and technical information

Invitae is a College of American Pathologists (CAP)-accredited and Clinical Laboratory Improvement Amendments (CLIA)-certified clinical diagnostic laboratory performing full-gene sequencing and deletion/duplication analysis using next-generation sequencing technology (NGS).

Our sequence analysis covers clinically important regions of each gene, including coding exons, +/- 10 base pairs of adjacent intronic sequence in the transcript listed below. In addition, analysis covers the select non-coding variants specifically defined in the table below. Any variants that fall outside these regions are not analyzed. Any specific limitations in the analysis of these genes are also listed in the table below.

Our analysis detects most intragenic deletions and duplications at single exon resolution. However, in rare situations, single-exon copy number events may not be analyzed due to inherent sequence properties or isolated reduction in data quality. If you are requesting the detection of a specific single-exon copy number variation, please contact Client Services before placing your order.

Gene Transcript reference Sequencing analysis Deletion/Duplication analysis
F9 NM_000133.3