Embden-Meyerhof defects /emb″den mī″ərhof/ [Gustav G. Embden, German biochemist, 1874–1933; Otto F. Meyerhof, German biochemist, 1884–1951] , a group of hereditary hemolytic anemias caused by enzyme deficiencies. The most common form of the disorder is a pyruvate kinase deficiency. The condition is characterized by an absence of spherocytes and the presence of small numbers of crenated erythrocytes. The trait is transmitted as an autosomal-recessive gene, and the hemolytic anemia occurs only in homozygotes.