Gert van der Hoek
In Memoriam - Editor, Senior Moderator
machinetranslated, edited a little
Mutations in the hemagglutinin protein.
From Norway viruses were first reported that had a mutation in
the HA gene
include involving a substitution at amino acid position 222 of the protein.
The mutation was detected in patient material from two fatal cases of
pandemic (H1N1)
2009-virus infections. A third case involved a patient with pneumonia.
The relevant D222G
(aspartic acid to glycine) substitution may affect the receptor specificity
as described
for the 1918 Spanish influenza virus (Stevens et al J. Mol. Biol. 355:1143-55, 2006)
where the mutation
correlates with a shift in receptor specificity of α (2-6)-linked
siaalzuren to
α (2-3)-linked siaalzuren. The latter receptors are strongly represented
in the lower
airways, which correlated with the development of a more severe pandemic (H1N1) 2009 --
viral infections
could explain.
In the Netherlands, this mutation was proved once and in the Ukraine
four times with fatal cases. The mutation is also found elsewhere, but unknown
is whether there
there was severe disease.
In addition,in the Netherlands and elsewhere,
two other mutations were observed
in the same position in the HA gene,
namely D222E (aspartic to glutamic acid)
and D222N (aspartic acid to asparagine) substitutions.
However, a correlation with the severity of the infection
and these mutations is not clear,
because it is frequently found even in less severe cases.
source:
INFLUENZA SURVEILLANCE-NEWSLETTER 2009/10
Published by:
National Influenza Center (NIC): Rotterdam (Erasmus MC), Bilthoven (RIVM),
Dutch Institute for Health Services Research (NIVEL),
Health Care Inspectorate (IGZ).
27.11 --
Mutations in the hemagglutinin protein.
From Norway viruses were first reported that had a mutation in
the HA gene
include involving a substitution at amino acid position 222 of the protein.
The mutation was detected in patient material from two fatal cases of
pandemic (H1N1)
2009-virus infections. A third case involved a patient with pneumonia.
The relevant D222G
(aspartic acid to glycine) substitution may affect the receptor specificity
as described
for the 1918 Spanish influenza virus (Stevens et al J. Mol. Biol. 355:1143-55, 2006)
where the mutation
correlates with a shift in receptor specificity of α (2-6)-linked
siaalzuren to
α (2-3)-linked siaalzuren. The latter receptors are strongly represented
in the lower
airways, which correlated with the development of a more severe pandemic (H1N1) 2009 --
viral infections
could explain.
In the Netherlands, this mutation was proved once and in the Ukraine
four times with fatal cases. The mutation is also found elsewhere, but unknown
is whether there
there was severe disease.
In addition,in the Netherlands and elsewhere,
two other mutations were observed
in the same position in the HA gene,
namely D222E (aspartic to glutamic acid)
and D222N (aspartic acid to asparagine) substitutions.
However, a correlation with the severity of the infection
and these mutations is not clear,
because it is frequently found even in less severe cases.
source:
INFLUENZA SURVEILLANCE-NEWSLETTER 2009/10
Published by:
National Influenza Center (NIC): Rotterdam (Erasmus MC), Bilthoven (RIVM),
Dutch Institute for Health Services Research (NIVEL),
Health Care Inspectorate (IGZ).
27.11 --