Major alterations in the composition of the cartilage extracellular matrix occur in joint disease, such as osteoarthrosis. The synthesis of cartilage intermediate layer protein (CILP), which was identified and purified from human articular cartilage, increases in early osteoarthrosis cartilage. The C-terminal 460 amino acids of the protein show 90% similarity to the pig ectonucleotide pyrophosphohydrolase NTPPHase; this region is preceded by a furin protease consensus cleavage site. Thus, the CILP gene is thought to encode a protein precursor for 2 different proteins, namely CILP and a homolog of NTPPHase.The RefSeq transcript and protein were derived from transcript and genomic sequence to make the sequence consistent with the reference genome assembly. The genomic coordinates used for the transcript record were based on alignments.