[Marble bones disease--a contribution to its course (author's transl)].

The two different forms of Osteopetrosis Albers-Schönberg are demonstrated by the respective reports on two typical cases. The autosomal dominant form has a late manifestation and is often discovered only by chance. The autosomal recessive form manifests itself in early infancy and often results in death during the first decade of life. There is no known therapy. Pathogenesis and pathophysiology cannot be explained with certainty; an insufficiency of osteoclasts as well as a disturbed ossification process have been postulated. With regard to the prognosis it is essential to realize other forms of osteopetrosis. The genetic aspects are pointed out, in particular their implication in advising families who wish to have further children.