Human hemoglobin has provided an excellent model for studying gene action at the molecular level in higher organisms. Much is now known about the genetics of normal human hemoglobin, and several disorders of hemoglobin synthesis have been well defined at both genetic and molecular levels. As judged by the early results of the application of newer techniques of gene mapping to human DNA, it seems probable that the next few years will see spectacular advances in the analysis of the hemoglobin genome and hence in our understanding of both normal and abnormal gene action in man.

This brief account summarizes what is known about the genetic control of normal human hemoglobin synthesis, outlines the disorders of hemoglobin synthesis which have been well characterized at the genetic and molecular levels, and attempts to define those areas where most information seems likely to be forthcoming from the application of some of the more recently described techniques for analysis of gene structure.