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Glite Dictionary
factor IX

factor IX

5.5
A blood protein that helps stop bleeding and whose lack causes hemophilia B, a disease with heavy bleeding
  • noun
  • Specialized
translation icon : factor IX
  • A deficiency in factor IX can lead to serious bleeding disorders, such as hemophilia B.

Examples

  • Schnieke et al. (1997) cloned three transgenic lambs (two of which survived) containing the human gene for clotting factor IX.

    Academic text (1999)

  • Doctors can test for factor IX levels to diagnose clotting disorders in patients.

  • Only those cells that had integrated the genes for neomycin resistance and, therefore, clotting factor IX survived and were used for nuclear transfer.

    Academic text (1999)

  • Individuals with low levels of factor IX may require regular treatments to prevent bleeding episodes.

Synonyms

Christmas factor
vsfactor IX
  • Specialized
6.5

A protein in the blood that helps blood form clots and stop bleeding

is the standard scientific numeric name for the same protein

Surface Forms

factor IX singular
factors IX plural

Morphology

factor + IX

The form 'factor IX' is compositionally understandable as 'factor number nine' from 'factor' (element) + 'IX' (nine), so learners can infer it's a named or numbered item. However, the specific medical sense — that it is a blood clotting protein whose deficiency causes hemophilia B — requires domain knowledge beyond knowing the constituents. Because the numbering cue is clear but the specialized referent is not derivable by a B1 learner, the expression is best classified as semi-transparent.

Etymology

Factor IX got its name when researchers listed the things the blood needs to 'clot' and gave each one a number, so this one was the ninth and labeled IX. Because it is a protein that helps the blood 'clot', not having enough factor IX causes hemophilia B.