A frameshift at codons 77/78 (-C): a novel beta-thalassemia mutation

We identified and characterized a novel beta-thalassemia (beta-thal) mutation due to a deletion of cytosine at codons 77/78 (-C) [CAC(His) CA- or CTG(Leu)--> -TG] found in a heterozygous state in four members of a Mexican family. The beta haplotype analysis performed on the family revealed that the frameshift at codons 77/78 (-C) mutation in this family is associated with haplotype V [- + - - - + ] and framework 2. Ten beta-thal alleles with a cytosine deletion are described at the Globin Gene Server, two of which are very near codon 77. The molecular pathology of beta-thal in the Mexican population has been shown to be heterogeneous, because some Mediterranean, Asian, private and rare alleles have been observed, a similar fact as has been observed in populations with a low frequency of beta-thal.