diff --git a/pom.xml b/pom.xml
index 54fdcb5..d101217 100644
--- a/pom.xml
+++ b/pom.xml
@@ -127,7 +127,7 @@
     <dependency>
       <groupId>com.google.cloud.genomics</groupId>
       <artifactId>google-genomics-utils</artifactId>
-      <version>v1beta2-0.36</version>
+      <version>v1beta2-0.37</version>
       <exclusions>
         <!-- Exclude an old version of guava which is being pulled
              in by a transitive dependency google-api-client 1.19.0 -->
diff --git a/src/main/java/com/google/cloud/genomics/dataflow/readers/ReadStreamer.java b/src/main/java/com/google/cloud/genomics/dataflow/readers/ReadStreamer.java
index dcf3643..109fabd 100644
--- a/src/main/java/com/google/cloud/genomics/dataflow/readers/ReadStreamer.java
+++ b/src/main/java/com/google/cloud/genomics/dataflow/readers/ReadStreamer.java
@@ -81,7 +81,7 @@ public void processElement(ProcessContext c) throws IOException, GeneralSecurity
       initializedShardCount.addValue(1);
       shardTimeMaxSec.addValue(0L);
       Stopwatch stopWatch = Stopwatch.createStarted();
-      Iterator<StreamReadsResponse> iter = new ReadStreamIterator(c.element(), auth, shardBoundary, fields);
+      Iterator<StreamReadsResponse> iter = ReadStreamIterator.enforceShardBoundary(auth, c.element(), shardBoundary, fields);
       while (iter.hasNext()) {
         StreamReadsResponse readResponse = iter.next();
         c.output(readResponse.getAlignmentsList());
diff --git a/src/main/java/com/google/cloud/genomics/dataflow/readers/VariantStreamer.java b/src/main/java/com/google/cloud/genomics/dataflow/readers/VariantStreamer.java
index 94ec6fa..8a56bfc 100644
--- a/src/main/java/com/google/cloud/genomics/dataflow/readers/VariantStreamer.java
+++ b/src/main/java/com/google/cloud/genomics/dataflow/readers/VariantStreamer.java
@@ -87,7 +87,7 @@ public void processElement(ProcessContext c) throws IOException, GeneralSecurity
       initializedShardCount.addValue(1);
       shardTimeMaxSec.addValue(0L);
       Stopwatch stopWatch = Stopwatch.createStarted();
-      Iterator<StreamVariantsResponse> iter = new VariantStreamIterator(c.element(), auth, shardBoundary, fields);
+      Iterator<StreamVariantsResponse> iter = VariantStreamIterator.enforceShardBoundary(auth, c.element(), shardBoundary, fields);
       while (iter.hasNext()) {
         StreamVariantsResponse variantResponse = iter.next();
         c.output(variantResponse.getVariantsList());