A New Hb Variant: Hb F Sardinia γ75 (e 19) Isoieucine→Threonine Found in a Family with Hb G Philadelphia, β-Chain Deficiency and a Lepore-Like Haemoglobin Indistinguishable from Hb A2

Abstract

A 59-year-old man with β -thalassaemia major is unusually well. He has no γ -chains in his haemoglobin but is heterozygous for the genes responsible for α^A and for α^G Philadelphia. In addition he is also heterozygous for the genes responsible for γ^F and a new γ-chain, γ⁷⁵ (E¹⁹) Ile – Thr, named γ^F.Sardinia. It was not possible to isolate the mutant γ-chain, but from the overall ratios of Gγ-:Aγ-Chain and γ⁷⁵Ile : γ⁷⁵ Thr_; it could be inferred that the mutation had presumably occured in the Gγ-chain. Some of the propositus’ siblings have high levels of Hb A₂, and it is suggested that they possibly carry a gene for a Lepore chain with the δβ -crossover after residue δ126.