diff --git a/mapdamage/rescale.py b/mapdamage/rescale.py
index 0a73772..ca71c3e 100644
--- a/mapdamage/rescale.py
+++ b/mapdamage/rescale.py
@@ -275,11 +275,12 @@ def rescale_qual_read(bam, read, ref, corr_prob,subs, debug = False,direction="b
     read.qual = new_qual
     # truncate this to 5 digits
     number_of_rescaled_bases = float("%.5f" % number_of_rescaled_bases)
-    # check if the read has a MR tag 
-    for tag in read.tags:
-        if tag[0] == "MR":
-            raise SystemExit("Read: %s already has a MR tag, can't rescale" % (read))
-    read.tags = read.tags + [("MR:f",number_of_rescaled_bases)]
+
+    if read.has_tag("MR"):
+        raise SystemExit("Read: %s already has a MR tag, can't rescale" % read)
+
+    read.set_tag("MR", number_of_rescaled_bases, 'f')
+
     return read
 
 
diff --git a/mapdamage/version.py b/mapdamage/version.py
index fd563f0..5d2b8ff 100644
--- a/mapdamage/version.py
+++ b/mapdamage/version.py
@@ -2,5 +2,4 @@
 try:
     from mapdamage._version import __version__
 except ImportError:
-    __version__ = "2.0.7"
-
+    __version__ = "2.0.8"
diff --git a/setup.py b/setup.py
index 4dee6b0..d0c70ca 100644
--- a/setup.py
+++ b/setup.py
@@ -55,7 +55,7 @@ def run(self):
 setup(
     cmdclass={'install': compileInstall},
     name='mapdamage',
-    version='2.0.7',
+    version='2.0.8',
     author='Aurélien Ginolhac, Mikkel Schubert, Hákon Jónsson',
     author_email='MSchubert@snm.ku.dk, jonsson.hakon@gmail.com',
     packages=['mapdamage'],