Fig. 1.
Schematic representation of apo(a). Based on amino acid sequence differences, the plasminogen-like K4 domain of apo(a) is formed by 10 distinct K4 types. K4 type 1 and types 3 to 10, are present as a single copy, whereas the K4 type 2 is present in a variable number of identical copies ranging from 3 to >40. In the figure insert is the complete amino acid sequence of K4 type 2.