Normal human fibroblasts incorporated into a collagen lattice reduce the size of that lattice over a period of time. Lattice size reduction or lattice contraction is directly related to initial cell number. When equal numbers of fibroblasts derived from patients with epidermolysis bullosa dystrophica recessive, (EBdr), are used, there is delayed lattice contraction. The EBdr fibroblasts have an altered cellular shape, when compared to normal cells, in that the EBdr cells fail to flatten out and elongate, but do attach to collagen fibers like normal fibroblasts. EBdr fibroblasts maintain a rounded shape with numerous filopodia radiating from the cell periphery and such filopodia are attached to the collagen fibers of the lattice. In monolayer tissue culture on glass surfaces, EBdr fibroblasts are three times more likely to grow over neighboring fibroblasts. EBdr cell filopodia structures are attached to the cell surfaces lying beneath them, which demonstrates another condition of altered anchorage attachment of EBdr fibroblasts.