Mutations in cartilage oligomeric matrix protein causing pseudoachondroplasia and multiple epiphyseal dysplasia affect binding of calcium and collagen I, II, and IX.

Mutations in type 3 repeats of cartilage oligomeric matrix protein (COMP) cause two skeletal dysplasias, pseudoachondroplasia (PSACH) and multiple epiphyseal dysplasia (MED). We expressed recombinant wild-type COMP that showed structural and functional properties identical to COMP isolated from cartilage. A fragment encompassing the eight type 3 repeats binds 14 calcium ions with moderate affinity and high cooperativity and presumably forms one large disulfide-bonded folding unit.

Systemic scleroderma. Multicenter trial of 1 year of treatment with recombinant interferon gamma.

Objective: To confirm significant improvement of the skin score in systemic sclerosis by treatment with interferon gamma in a larger group of patients and to investigate on a molecular level the influence of interferon gamma on collagen type I messenger RNA expression.

Design: Open, noncontrolled multicenter study.

Setting: Five outpatient clinics specializing in the care of systemic scleroderma.

Quantitative analysis of alpha 1 (I) procollagen transcripts in vivo by competitive polymerase chain reaction.

Due to the limited amount of RNA obtainable from punch biopsies, few data exist on the human alpha 1 (I) procollagen mRNA steady state level in vivo. Therefore, we established a competitive PCR method to quantitate this mRNA in human biopsies. In our approach, the target template and the standard share the same sequence except for a 69 bp deletion, thus competing for the same primer pair and subsequently amplifying at the same rate.