3.4.21.B12	E77A	the mutation completely abolishes the inhibitory effect of Zn2+ for hK4	
3.4.21.B12	E77A	zinc-independent	
3.4.21.B12	H25A	the mutation completely abolishes the inhibitory effect of Zn2+ for hK4	
3.4.21.B12	H25A	zinc-independent	
3.4.21.B12	additional information	naturally occuring gene mutation G214A results in a truncated enzyme that lacks residue S207 of the catalytic triad. Mutation affects tooth enamel formation causing the enamel crystallites to grow incompletely in thickness or width but to normal length, i.e. autosomal recessive hypomaturation amelogenesis imperfecta	
3.4.21.B12	additional information	KLK-4 mutant (g.2142G>A), enamel is of normal thickness but opaque throughout its width compared with normal enamel. Enamel has a normal prismatic structure and generally a well-organized and discernable crystallite composition. In some areas, globular structures are present where crystallites are not discernable or appear to have an altered morphology. The KLK-4 mutant enamel has an increased protein content compared with normal enamel