diff --git a/biodata-models/src/main/java/org/opencb/biodata/models/core/Snp.java b/biodata-models/src/main/java/org/opencb/biodata/models/core/Snp.java
new file mode 100644
index 00000000..8f8cc712
--- /dev/null
+++ b/biodata-models/src/main/java/org/opencb/biodata/models/core/Snp.java
@@ -0,0 +1,147 @@
+/*
+ * <!--
+ *   ~ Copyright 2015-2017 OpenCB
+ *   ~
+ *   ~ Licensed under the Apache License, Version 2.0 (the "License");
+ *   ~ you may not use this file except in compliance with the License.
+ *   ~ You may obtain a copy of the License at
+ *   ~
+ *   ~     http://www.apache.org/licenses/LICENSE-2.0
+ *   ~
+ *   ~ Unless required by applicable law or agreed to in writing, software
+ *   ~ distributed under the License is distributed on an "AS IS" BASIS,
+ *   ~ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *   ~ See the License for the specific language governing permissions and
+ *   ~ limitations under the License.
+ *   -->
+ *
+ */
+
+package org.opencb.biodata.models.core;
+
+import java.util.List;
+
+public class Snp {
+    private String id;
+    private String chromosome;
+    private int position;
+    private String reference;
+    private List<String> alternates;
+    private String type;
+    private String source;
+    private String version;
+    private SnpAnnotation annotation;
+
+    public Snp() {
+    }
+
+    public Snp(String id, String chromosome, int position, String reference, List<String> alternates, String type,
+               String source, String version, SnpAnnotation annotation) {
+        this.id = id;
+        this.chromosome = chromosome;
+        this.position = position;
+        this.reference = reference;
+        this.alternates = alternates;
+        this.type = type;
+        this.source = source;
+        this.version = version;
+        this.annotation = annotation;
+    }
+
+    @Override
+    public String toString() {
+        final StringBuilder sb = new StringBuilder("Snp{");
+        sb.append("id='").append(id).append('\'');
+        sb.append(", chromosome='").append(chromosome).append('\'');
+        sb.append(", position=").append(position);
+        sb.append(", reference='").append(reference).append('\'');
+        sb.append(", alternates=").append(alternates);
+        sb.append(", type='").append(type).append('\'');
+        sb.append(", source='").append(source).append('\'');
+        sb.append(", version='").append(version).append('\'');
+        sb.append(", annotation=").append(annotation);
+        sb.append('}');
+        return sb.toString();
+    }
+
+    public String getId() {
+        return id;
+    }
+
+    public Snp setId(String id) {
+        this.id = id;
+        return this;
+    }
+
+    public String getChromosome() {
+        return chromosome;
+    }
+
+    public Snp setChromosome(String chromosome) {
+        this.chromosome = chromosome;
+        return this;
+    }
+
+    public int getPosition() {
+        return position;
+    }
+
+    public Snp setPosition(int position) {
+        this.position = position;
+        return this;
+    }
+
+    public String getReference() {
+        return reference;
+    }
+
+    public Snp setReference(String reference) {
+        this.reference = reference;
+        return this;
+    }
+
+    public List<String> getAlternates() {
+        return alternates;
+    }
+
+    public Snp setAlternates(List<String> alternates) {
+        this.alternates = alternates;
+        return this;
+    }
+
+    public String getType() {
+        return type;
+    }
+
+    public Snp setType(String type) {
+        this.type = type;
+        return this;
+    }
+
+    public String getSource() {
+        return source;
+    }
+
+    public Snp setSource(String source) {
+        this.source = source;
+        return this;
+    }
+
+    public String getVersion() {
+        return version;
+    }
+
+    public Snp setVersion(String version) {
+        this.version = version;
+        return this;
+    }
+
+    public SnpAnnotation getAnnotation() {
+        return annotation;
+    }
+
+    public Snp setAnnotation(SnpAnnotation annotation) {
+        this.annotation = annotation;
+        return this;
+    }
+}
diff --git a/biodata-models/src/main/java/org/opencb/biodata/models/core/SnpAnnotation.java b/biodata-models/src/main/java/org/opencb/biodata/models/core/SnpAnnotation.java
new file mode 100644
index 00000000..16fab718
--- /dev/null
+++ b/biodata-models/src/main/java/org/opencb/biodata/models/core/SnpAnnotation.java
@@ -0,0 +1,79 @@
+/*
+ * <!--
+ *   ~ Copyright 2015-2017 OpenCB
+ *   ~
+ *   ~ Licensed under the Apache License, Version 2.0 (the "License");
+ *   ~ you may not use this file except in compliance with the License.
+ *   ~ You may obtain a copy of the License at
+ *   ~
+ *   ~     http://www.apache.org/licenses/LICENSE-2.0
+ *   ~
+ *   ~ Unless required by applicable law or agreed to in writing, software
+ *   ~ distributed under the License is distributed on an "AS IS" BASIS,
+ *   ~ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *   ~ See the License for the specific language governing permissions and
+ *   ~ limitations under the License.
+ *   -->
+ *
+ */
+
+package org.opencb.biodata.models.core;
+
+import org.opencb.biodata.models.variant.avro.PopulationFrequency;
+
+import java.util.List;
+import java.util.Map;
+
+public class SnpAnnotation {
+
+    private List<String> flags;
+    private String gene;
+    private List<PopulationFrequency> populationFrequencies;
+    private Map<String, Object> additionalAttributes;
+
+    public SnpAnnotation() {
+    }
+
+    public SnpAnnotation(List<String> flags, String gene, List<PopulationFrequency> populationFrequencies, Map<String, Object> additionalAttributes) {
+        this.flags = flags;
+        this.gene = gene;
+        this.populationFrequencies = populationFrequencies;
+        this.additionalAttributes = additionalAttributes;
+    }
+
+    public List<String> getFlags() {
+        return flags;
+    }
+
+    public SnpAnnotation setFlags(List<String> flags) {
+        this.flags = flags;
+        return this;
+    }
+
+    public String getGene() {
+        return gene;
+    }
+
+    public SnpAnnotation setGene(String gene) {
+        this.gene = gene;
+        return this;
+    }
+
+    public List<PopulationFrequency> getPopulationFrequencies() {
+        return populationFrequencies;
+    }
+
+    public SnpAnnotation setPopulationFrequencies(List<PopulationFrequency> populationFrequencies) {
+        this.populationFrequencies = populationFrequencies;
+        return this;
+    }
+
+    public Map<String, Object> getAdditionalAttributes() {
+        return additionalAttributes;
+    }
+
+    public SnpAnnotation setAdditionalAttributes(Map<String, Object> additionalAttributes) {
+        this.additionalAttributes = additionalAttributes;
+        return this;
+    }
+}
diff --git a/biodata-tools/src/main/java/org/opencb/biodata/tools/alignment/BamManager.java b/biodata-tools/src/main/java/org/opencb/biodata/tools/alignment/BamManager.java
index 895767e9..54b84cc0 100644
--- a/biodata-tools/src/main/java/org/opencb/biodata/tools/alignment/BamManager.java
+++ b/biodata-tools/src/main/java/org/opencb/biodata/tools/alignment/BamManager.java
@@ -49,6 +49,7 @@
 import java.nio.file.Paths;
 import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.Collections;
 import java.util.List;
 
 /**
@@ -62,7 +63,7 @@ public class BamManager implements AutoCloseable {
 
     public static final int DEFAULT_WINDOW_SIZE = 1;
     public static final int MAX_NUM_RECORDS = 50000;
-    public static final int MAX_REGION_COVERAGE = 100000;
+    public static final int MAX_REGION_COVERAGE = 500000;
     public static final String COVERAGE_BIGWIG_EXTENSION = ".bw";
 
     private Logger logger;
@@ -191,7 +192,10 @@ public Path calculateBigWigCoverage(Path bigWigPath, int windowSize) throws IOEx
         return bigWigPath;
     }
 
-
+    /**
+     * @deprecated (since getFileHeader().getTextHeader() is deprecated !)
+     */
+    @Deprecated
     public String header() {
         return samReader.getFileHeader().getTextHeader();
     }
@@ -338,7 +342,7 @@ public List<Chunk> getChunks(Region region) {
             BAMIndex index = samReader.indexing().getIndex();
             return index.getSpanOverlapping(sequenceIndex, start, end).getChunks();
         }
-        return null;
+        return Collections.emptyList();
     }
 
     public List<String> getBreakpoints(Region region) throws IOException {
@@ -378,7 +382,7 @@ public List<String> getBreakpoints(Region region) throws IOException {
                 }
             }
         }
-        return null;
+        return Collections.emptyList();
     }
 
     /**
@@ -445,7 +449,7 @@ public AlignmentGlobalStats stats(Region region, AlignmentFilters<SAMRecord> fil
         return calculateGlobalStats(iterator(region, filters, options));
     }
 
-    private AlignmentGlobalStats calculateGlobalStats(BamIterator<SAMRecord> iterator) throws IOException {
+    private AlignmentGlobalStats calculateGlobalStats(BamIterator<SAMRecord> iterator) {
         AlignmentGlobalStats alignmentGlobalStats = new AlignmentGlobalStats();
         SamRecordAlignmentGlobalStatsCalculator calculator = new SamRecordAlignmentGlobalStatsCalculator();
         while (iterator.hasNext()) {