Fetal hemoglobin variants identified in adults through restriction
endonuclease gene mapping methodology
T Nakatsuji, MS Burnley and TH Huisman
It has been found possible to detect the presence of some gamma chain
abnormal fetal hemoglobins in adults through analysis of genomic DNA with
selected restriction endonucleases. These variants are Hb F-Hull (A gamma
121Glu----Lys) which was observed in eight adult members of five families,
Hb F-Pendergrass (A gamma 36Pro----Arg) in five adult members of one
family, and Hb F-Port Royal (G gamma 125Glu----Ala) in 32 adult members of
17 families. The analyses were extended to include haplotyping, which
involved 12 different restriction sites. The Hb F- Port Royal anomaly was
only present on a chromosome with two G gamma genes (the 5'-G gamma-G
gamma-3' globin gene arrangement) which may have arisen through gene
conversion or point mutations. It appears likely that the mutation
resulting in the 125Glu----Ala substitution occurred once on a 5'-G gamma-G
gamma-3' chromosome, while additional base substitutions, gene conversions,
and/or cross-over events are responsible for the association of the F-Port
Royal anomaly with different chromosomes, as characterized by different
haplotypes.
Volume 66,
Issue 4,
pp. 803-807,
10/01/1985
Copyright © 1985 by The American Society of Hematology
