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diff --git a/src/main/java/org/apache/commons/math/genetics/BinaryMutation.java b/src/main/java/org/apache/commons/math/genetics/BinaryMutation.java
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+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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.apache.commons.math.genetics;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * Mutation for {@link BinaryChromosome}s. Randomly changes one gene.
+ *
+ * @version $Revision: 811685 $ $Date: 2009-09-05 19:36:48 +0200 (sam. 05 sept. 2009) $
+ * @since 2.0
+ */
+public class BinaryMutation implements MutationPolicy {
+
+    /**
+     * Mutate the given chromosome. Randomly changes one gene.
+     * @param original the original chromosome.
+     * @return the mutated chromomsome.
+     */
+    public Chromosome mutate(Chromosome original) {
+        if (!(original instanceof BinaryChromosome)) {
+            throw new IllegalArgumentException("Binary mutation works on BinaryChromosome only.");
+        }
+
+        BinaryChromosome origChrom = (BinaryChromosome) original;
+        List<Integer> newRepr = new ArrayList<Integer>(origChrom.getRepresentation());
+
+        // randomly select a gene
+        int geneIndex = GeneticAlgorithm.getRandomGenerator().nextInt(origChrom.getLength());
+        // and change it
+        newRepr.set(geneIndex, origChrom.getRepresentation().get(geneIndex) == 0 ? 1 : 0);
+
+        Chromosome newChrom = origChrom.newFixedLengthChromosome(newRepr);
+        return newChrom;
+    }
+
+}