SOME CATALYTIC ASPECTS OF DISEASE AND DRUGS 223 



beat and size of heart; (6) size of endocrine glands, etc. 7 A type of 

 dwarfism in the house mouse is caused by a simple recessive mutation 

 which, while not affecting secretion of the gonadotropic hormone by 

 the anterior pituitary, interferes with secretion of its growth-promoting 

 hormone. H. Griineberg 8 lists the following effects of this mutation: 

 (1) endocrine malfunction; (2) adult weight about one-quarter of nor- 

 mal; (3) complete sterility in both sexes; (4) histological abnormalities 

 in interior lobe of the pituitary; (5) small, abnormal thyroids; (6) sub- 

 normal metabolism; (7) infantile structure of thymus, adrenals and 

 gonads; (8) subnormal viability. 



Enough has been said to show that there is much yet to be 

 learned about the real underlying causes of predisposition to dis- 

 ease (diathesis). Uric acid diathesis was defined as "a condition of 

 the system in which uric acid is deposited in the joints." In Sir 

 William Osier's great book 9 the following appears in the discus- 

 sion of gout: 



"Uric acid, in the body almost completely in the form of urates, 

 is the end-product of purine metabolism in man, just as urea is 

 the end-product of nitrogenous substances of amino-acid and py- 

 rimidine origin. In man the end product of purine breakdown 

 is excreted as urate, there being no enzyme in man to break it 

 down further to allantoin, as occurs in most mammals." Curi- 

 ously enough, Dalmatian coach dogs differ from most other dogs 

 in their inability to convert uric acid to allantoin, and excrete 

 over four times as much uric acid daily per unit of body weight 

 as do other dogs. H. C. Trimble and C. E. Keeler 10 showed that 

 this characteristic is determined by a recessive mutation not linked 

 with the spotting characteristic of the Dalmatian breed. 



For the most part, the great numbers of diseases described 

 in Osier's book classify the data as follows: etiology; pathology 

 (where known); symptoms; prognosis; diagnosis; treatment. For 

 some diseases prophylaxis and epidemology are given, and only 

 rarely pathological physiology, although from the latter the clini- 

 cal syndrome emerges at higher structural levels. A classification 

 of diseases based on physiological abnormalities traced to biocata- 

 lyst lack or deviation might be helpful not only in understanding 

 and treating diseases, but also in understanding the mode of ac- 

 tion of drugs which in many cases affect biocatalysts directly. 

 Apparently no such classification of diseases exists, and the fol- 

 lowing resume is given of a few instances where existing knowl- 



