diff --git a/uk/ac/sanger/artemis/components/variant/VCFRecord.java b/uk/ac/sanger/artemis/components/variant/VCFRecord.java
index b8e6f77b61ded57f0718fb31ce2e005479a68689..6a55e784c38d68d0b07a16c14e23b36a855e955f 100644
--- a/uk/ac/sanger/artemis/components/variant/VCFRecord.java
+++ b/uk/ac/sanger/artemis/components/variant/VCFRecord.java
@@ -45,7 +45,7 @@ class VCFRecord
   private String format;
   private String data[][];
   private short synFlag = -1;
-  protected static Pattern MULTI_ALLELE_PATTERN = Pattern.compile("^[AGCT]+,[AGCT,]+$");
+  protected static Pattern MULTI_ALLELE_PATTERN = Pattern.compile("^[AGCTagct]+,[AGCTacgt,]+$");
   protected static Pattern COLON_PATTERN = Pattern.compile(":");
   protected static Pattern SEMICOLON_PATTERN = Pattern.compile(";");