A New, Electrophoretically Silent, Fetal Hemoglobin Variant: Hb F-Calabria [^Gγ118(GH1)Phe→Leu]

Abstract

Hb F-Calabria [^Gγ118(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 elect rophoresis of dissociated globin chains in the presence of Triton X-100, and by reversed phase high performance liquid chromatography) as a slightly hydrophilic ^Gγ chain. Sequencing of the polymerase chain reaction-amplified exon 3 of the ^Gγ-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 40^th example of a ^Gγ chain variant.