public void TestMismatches () {
			Sequence seq = new Sequence( AlphabetType.DNA, "actg" );
			Assert.AreEqual( 0, seq.Mismatches( 2, new Sequence( AlphabetType.DNA, "ctg" ) ) );
			Assert.AreEqual( 1, seq.Mismatches( 2, new Sequence( AlphabetType.DNA, "cta" ) ) );
			Assert.AreEqual( 3, seq.Mismatches( 1, new Sequence( AlphabetType.DNA, "ctg" ) ) );
		}