Hb-M "Hyde Park": a de novo mutation, identified by mass spectrometry and DNA analysis.
BACKGROUND
Structural hemoglobinopathies usually are inherited as autosomic dominant traits; de novo mutations are uncommon. Analytical and preparative procedures for the characterization of an abnormal hemoglobin are complex and time-consuming. Mass spectrometer analysis allows a rapid identification of the amino acid substitution.


RESULTS
A cyanotic 7-year-old girl was found to have 16% methemoglobin. Laboratory data showed the presence of an abnormal hemoglobin, which was isolated by collecting the abnormal peak from DEAE and globin chains from CM52. The amino acid substitution was rapidly identified by FAB mass spectroscopic analysis, leading to the recognition of HbM Hyde Park. These data were confirmed by molecular analysis (Southern blot and DNA sequencing). Neither the parents nor a sister showed any abnormality; non-paternity was excluded by blood group serology and HLA typing.


CONCLUSIONS
This is a case of HbM Hyde-Park arising as a de novo mutation. FAB mass spectroscopic analysis is a rapid and useful analytical method for identifying aminoacid substitution.
Rotoli
B
B
Divisione di Ematologia, 2a Facoltà Medica, Università di Napoli, Italy.
Camera
A
A
Fontana
R
R
Frigeri
F
F
Pandolfi
G
G
Vecchione
R
R
Poggi
V
V
Longo
G
G
Carestia
C
C
De Angioletti
M
M
D015139:Blotting, Southern; D002648:Child; D003490:Cyanosis / Q000235:genetics*; D004252:DNA Mutational Analysis; D005260:Female; D006449:Hemoglobin M / Q000235:genetics*; D006453:Hemoglobinopathies / Q000235:genetics*; D006801:Humans; D013058:Mass Spectrometry; D009154:Mutation; D010108:Oxyhemoglobins / Q000235:genetics
D010108:Oxyhemoglobins; C056016:hemoglobin M Akita; D006449:Hemoglobin M