A second observation of the rare frameshift mutation in the β-globin gene: codon 46 (+A) (Hbb:c.138_139insA).

The preparation of a prenatal diagnosis in a family of North-African origin in which a child received a bone marrow transplant for β-thalassemia major (β-TM), prompted us to make the molecular diagnosis in the parents and siblings. Molecular and phenotype assays were carried on blood samples from the parents and the proband's sister. The father, a 45-year-old man, was found to be heterozygous for a rare mutation in exon 2 [codon 46 (+A), HBB:c.