A new, electrophoretically silent, fetal hemoglobin variant: Hb F-Calabria [Ggamma118(GH1)Phe-->Leu]

Hb F-Calabria [Ggamma118(GH1)Phe-->Leu] is a new fetal hemoglobin variant that was found during routine screening for abnormal hemoglobins in a newborn of Calabrian (Southern Italy) ancestry. The variant chain was identified (acid urea gel electrophoresis of dissociated globin chains in the presence of Triton X-100, and by reversed phase high performance liquid chromatography) as a slightly hydrophilic Ggamma chain. Sequencing of the polymerase chain reaction-amplified exon 3 of the Ggamma-globin gene demonstrated the TTC-->CTC mutation at codon 118 leading to the Phe-->Leu conservative substitution at position GH1. A molecular modeling study supports that the variant might not have clinical implications. This is the 40th example of a Ggamma chain variant.