Abstract
The subjects of this study were a hereditary typical acatalasemia and a hereditary atypical acatalasemia. In the latter case, the children did not show hypocatala-semia but one of the cousins proved to be hypocatalasemia. The abdominal muscle and the vermiform appendix from the case of typical acatalasemia had only a minute catalase activity. The liver from the case of atypical acatalasemia indicated a moderate catalase activity and catalase protein was observed in it.
