Fig. 2
From: The usefulness of lactate dehydrogenase measurements in current oncological practice
Scheme presenting LDH isoforms. The ldha and ldhb genes encode LDHA and LDHB polypeptide subunits. The combinations of these two subunits into active tetramers results in the five LDH isoforms B4, A1B3, A2B2, A3B1 and A4, named LD1 to LD5, respectively. A third type of LDH subunit, known as C, is encoded by the ldhc gene. The LDHC subunit assembles only into homotetramers to form the LD6 (or LDX) isoform. The multiplicity of LDH molecular forms can be revealed on the basis of their different mobility in gel electrophoresis. The LD1 isoform has the highest and LD5 the lowest migration rate towards the anode, as demonstrated in zymograms