diff --git a/mrdna/model/dna_sequence.py b/mrdna/model/dna_sequence.py
index 2d120ec018bca77a14f697a6b0d4a66973f345e6..520d3b22db2c1180a024a00d2c470bbb86c60cb2 100644
--- a/mrdna/model/dna_sequence.py
+++ b/mrdna/model/dna_sequence.py
@@ -6,7 +6,7 @@ def read_sequence_file(sequenceFile=_m13_path):
     with open(sequenceFile) as ch:
         for l in ch:
             l = l.strip().replace(" ", "")
-            if l[0] in (";","#"): continue
+            if len(l) == 0 or l[0] in (";","#"): continue
             seq.extend([c.upper() for c in l])
     return list(seq)