Serum gamma-glutamyltransferase fractions in myotonic dystrophy type I: differences with healthy subjects and patients with liver disease

Clin Biochem. 2010 Oct;43(15):1246-8. doi: 10.1016/j.clinbiochem.2010.07.018. Epub 2010 Aug 4.


Objectives: Elevation of serum gamma-glutamyltransferase (GGT), in absence of a clinically significant liver damage, is often found in Myotonic Dystrophy type-1 (DM1). In this study we investigated if a specific GGT fraction pattern is present in DM1.

Designs and methods: We compared total and fractional GGT values (b-, m-, s-, f-GGT) among patients with DM1 or liver disease (LD) and healthy subjects (HS).

Results: The increase of GGT in DM1 and LD, vs HS, was mainly due to s-GGT (median: 32.7; 66.7; and 7.9 U/L, respectively), and b-GGT (8.5; 18.9; and 2.1 U/L). The subset of DM1 patients matched with HS with corresponding serum GGT showed higher b-GGT (6.0 vs 4.2 U/L).

Conclusions: DM1 patients with normal total GGT values showed an alteration of the production and release in the blood of GGT fractions. Since increased s-GGT is also found in LD, a sub-clinical liver damage likely occurs in DM1 subjects apparently free of liver disease.

MeSH terms

  • Adult
  • Case-Control Studies
  • Chemical Fractionation
  • Female
  • Health*
  • Humans
  • Liver Diseases / blood*
  • Liver Diseases / enzymology*
  • Male
  • Middle Aged
  • Myotonic Dystrophy / blood*
  • Myotonic Dystrophy / enzymology*
  • gamma-Glutamyltransferase / blood*


  • gamma-Glutamyltransferase
  • gamma-glutamyltransferase, human