Table 3.

Observed range of haemoglobin S percentage in individuals with sickle cell trait divided into three groups by inspection of the data, with of without globin chain synthesis data, but without analysis of globin genes

N	Postulated genotype			Method	Ref
	αα/αα	−α/αα	−α/−α
				Electrophoresis on polyacrylamide gel or cellulose acetate followed by elution	5
NS	37–50	30–36	20–29	NS	6
75	>38	31–38	<31	Column chromatography	7
56	>38	31–38	<31	Column chromatography	8
171	35–45	28–35	<28	Cellulose acetate electrophoresis and elution	9

NS, not specified.