Figure 1

Reported mutations of CTSK. (A) Distribution of the CTSK gene and polypeptide mutations. The genomic structure of the CTSK gene with 8 exons (purple boxes numbered 1-8) is shown in the top half. The bottom half illustrates the schematic representation of the polypeptide comprising a 15-amino acid preregion (yellow box), a 99-residue proregion (light blue boxes), and a 215-amino acid mature domain (orange boxes). A total of 23 missense mutations (black type) are represented at the top of the gene diagram, while frame-shift mutations (red type), nonsense mutations (light green type), splicing mutations (blue type), and termination codon mutations (yellow type) are at the bottom. (B) Frequency of different mutations. The height of each bar represents the number of afflicted families. #: Both mutations in the Glu70 residue. ##: Both mutations in the Ala277 residue. (C) The type of reported CTSK mutations. The mutations reported in pycnodysostosis patients consist of 23 missense mutations, 4 frame-shift mutations, 3 nonsense mutations, 2 splicing mutations, and 1 termination codon mutation. (D) Distribution of reported CTSK mutations. A total of 69.70% of the mutations occurred in the mature domain, 24.24% in the proregion, and 6.06% in the preregion.