Is haemoglobin G alpha Philadelphia linked to alpha-thalassaemia?

The question, "Is Hb G alpha Philadelphia linked to alpha-thalassaemia?" was first posed because the abnormal haemoglobin is found in heterozygotes at a concentration greater than 25%, the proportion predicted from a 4 alpha-chain gene model. Globin chain biosynthesis was studied in a West Indian family in which one parent had beta + thalassaemia and the other was heterozygous for the G alpha Philadelphia chain gene. The former had a globin chain production ratio alpha/beta well above 1, while the latter had a ratio significantly less than 1.

Homozygous haemoglobin D Punjab.

A homozygote for the gene controlling Hb D Punjab is described. The diagnosis is supported by the peptide analysis of the haemoglobin and the examination of both parents. There was no anaemia or reticulocytosis and there was balanced synthesis of both the alphaA- and betaD-globin chains in reticulocytes.