288 



CHAPTER 32 



FIGURE 32-3. The ^'fingerprints''' of hemoglobin obtained following trypsin 



treatment. (Courtesy of V. M. Ingram, from C. Baglioni, Biochim. Biophys. 



Acta, 48:392-396, 1961.) 



which cause a single amino acid located in 

 different positions in the /3 chain to be re- 

 placed by other single amino acids, the de- 

 tailed genetic basis for the different mutants 

 is not known as precisely, although in some 

 cases the mutants are believed to be different 

 alleles of the same recon. The available 

 evidence is consistent with the view that all 

 these mutants are at least on the same chro- 

 mosome. 



Still other kinds of hemoglobin have been 

 found in which the amino acid sequence in 

 the a chain has been modified. This is true 

 for hemoolobin I (in which a change occurs in 

 peptide 23), and for hemoglobin '''Hopkins-2." 



A person homozygous for hemoglobin A 

 has a molecule describable as af0-^ (see Fig- 

 ure 32-4), one homozygous for the recon for 

 sickling can be described a.t/3.2, and one ho- 

 mozygous for the production of hemoglobin I 



