MutaGEL® Collagen (AS) kit is an amplification refractionary mutation system (ARMS) containing two sets of primers for both allelspecific sequences within the human collagen gene COL1A1. The allel specific primers can be used directly for PCR with extracted DNA and generate amplificates only in case of presence of one from both sequence possibilities (normal or pathogen). The resulting amplification products are subsequently identified with gelelectrophoretic methods. If there is no specific allel-product detectable, the correct PCR procedure is proved by an internal control. The present genotype of unknown samples is interpreted by detection of corresponding DNA-amplificates for normal- and pathogenconstellation in two separate lanes of the gel (method by Dr. Essrich, Biologisches Labor, Denzlingen).