diff --git a/DESCRIPTION b/DESCRIPTION
index 0bc8e16..36268c6 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -1,6 +1,6 @@
 Package: Gviz
 Title: Plotting data and annotation information along genomic coordinates
-Version: 1.44.1
+Version: 1.44.2
 Authors@R: c(person("Florian", "Hahne", role="aut"),
 	 person("Steffen", "Durinck", role="aut"),
 	 person("Robert", "Ivanek", role=c("aut", "cre"), 
diff --git a/R/utils.R b/R/utils.R
index 2070577..3e67bfc 100644
--- a/R/utils.R
+++ b/R/utils.R
@@ -2186,6 +2186,7 @@ availableDefaultMapping <- function(file, trackType) {
     if (length(range)) {
         alg <- extractAlignmentRangesOnReference(range$cigar, drop.D.ranges = drop.D.ranges)
         rp <- elementNROWS(alg)
+        if (is.null(range$flag)) range$flag <-  as.character(NA)
         range <- sort(GRanges(
             seqnames = rep(seqnames(range), rp), strand = rep("*", sum(rp)), ranges = shift(unlist(alg), rep(start(range), rp) - 1),
             id = rep(range$id, rp), entityId = rep(seq_along(rp), rp), cigar = rep(range$cigar, rp), md = rep(range$md, rp),