Human Phenotype Ontology 
Grandparent Node:
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Abnormality of the coagulation cascade (HP:0003256)help
Parent Node:
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Abnormality of the intrinsic pathway (HP:0010989)help
..Starting node
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Reduced factor IX activity (HP:0011858)help
Term ID: 11858
Name: Reduced factor IX activity
Synonym: Low factor IX activity
Definition: Decreased activity of coagulation factor IX. Factor IX, which itself is activated by factor Xa or factor VIIa to form factor IXa, activates factor X into factor Xa.
Comments:
Reference: HP:0011858
Genes and Diseases:
 
       Child Nodes:

 Sister Nodes: 
..expandAbnormal factor VIII activity (HP:0030976) help
..expandReduced antithrombin III activity (HP:0001976) help
..expandReduced factor XI activity (HP:0001929) help
..expandReduced factor XII activity (HP:0004841) help
..expandReduced kininogen activity (HP:0005527) help


Genes (6) :F9 GGCX MGAT2 PMM2 SLC37A4 VKORC1

Diseases (7) :OMIM:306900 OMIM:610842 OMIM:277450 OMIM:212066 ORPHA:79318 OMIM:619525 OMIM:607473
 

Human Phenotype Ontology(HPO) is developed by the Human Phenotype Ontology Consortium. The version used here is December 15 2022 release.