title: Hemoglobin A3
text: # Hemoglobin A3
  
  Hemoglobin A3 is a predominantly historic term for a fraction of normal hemoglobin molecules that is seen when hemoglobin is separated out using starch block electrophoresis. These Hemoglobin molecules are non-enzymatic modifications of the hemoglobin molecules and they encompass $hemoglobin_{A1c},$ $Hb_{1a}$ (both the subtypes $Hb_{1a1}$ and $Hb_{1a2})$ and $Hb_{1b}.$
  
  As these Hemoglobin subtypes are formed over time, they are found more prevalent in older red cells.
  
  