Alkaptonuria 



JACOB ROSENBLOOM 



PITTSBURGH 



MAX KAHN 



NEW YOBK 



Nature sometimes betrays her workings in her playful moods. It is 

 as if she tires of perpetually keeping her mysteries dark, and slightly 

 opens the veil for us to glance and see her exquisite, complicated methods. 

 We glance and are much instructed, guessing what we cannot perceive 

 and sometimes constructing a whole scientific philosophy of the mechan- 

 isms of life. Such an insight into the catabolic processes of the human 

 being is obtained by the study of the inborn error of metabolism known 

 as alkaptonuria. 



The condition is a very rare one and altogether unfraught with 

 danger. The patient comes complaining that he stains his laundry 

 black, or he becomes frightened, should he be an observant individual at 

 the coal black hue that his urine assumes upon standing. Or it may be 

 that he is rejected for insurance, because the examiner found a reduc- 

 ing substance in the urine. It is true that the reduction of Fehling 

 solution is not as typical as the one obtained with glucose; nor is the 

 bismuth in Nylander's solution reduced, although darkening occurs. This 

 urine upon being treated with an alkali will turn intensely black. It 

 is this affinity for alkalies that has won for it the name of alkapton. 

 The urine does not turn the polarized ray of light, nor does it ferment. 

 With ferric chlorid an intense blue color is obtained. 



Garrod, in his Croonian lectures, pointed out that this disturbance 

 was noted long ago. In the books of Scribonius (1584), of Schenk (1609), 

 and of Lusitanus (1649) instances are described of patients who suf- 

 fered with the anomaly of micturating black urine. In 1823, Alexander 

 Marcet(&) reported the case of an infant whose urine became darker on 

 standing, turned black with alkalies, and stained the napkins and linens. 



One would think from the evidence at hand that alkaptonuria is a 

 Mendelian recessive character. According to Garrod, who has collected 

 the instances of alkaptonuria in certain families, the figures, though not 

 accurately corresponding to the Mendelian law, still show a close rela- 

 tionship to it, while Bateson and Punnett are convinced that alkapto- 

 nuria is a rare recessive character in the Mendelian sense. 



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