Περίληψη:
We report a new type of non-deletional hereditary persistence of fetal
hemoglobin that is due to a C –> T transition at position -158,
relative to the Cap site of the human A gamma-globin gene. This mutation
was identified in three unrelated adult cases presenting slightly
elevated levels of fetal hemoglobin (Hb F), i.e. 2.9-5.1%, and normal
hematological indices. Our sequencing results, from both polymerase
chain reaction-amplified and subcloned DNA fragments, indicate that the
A gamma - 158C –> T mutation occurred by two independent gene
conversion events in the three cases studied. In addition, hematological
and molecular data, including restriction fragment length polymorphism
haplotyping in the beta-globin gene cluster, extended haplotype analysis
inside the gamma-globin gene region and routine analysis of three tandem
repeat loci (D1S80, 3’-HVR/apoB and F8vWf), led us to conclude that the
A gamma - 158C –> T mutation in one of the three cases occurred
recently in the parental germ line (P=99.47%), representing the first
example of a de novo gene conversion event identified in humans.
Συγγραφείς:
Patrinos, GP
Kollia, P
Loutradi-Anagnostou, A
Loukopoulos, D
and Papadakis, MN
