code: public static boolean isNonAmbNucleotideSequence(String sequence) {
  	sequence = SequenceUtil.cleanSequence(sequence);
  	if (SequenceUtil.DIGIT.matcher(sequence).find()) {
  		return false;
  	}
  	if (SequenceUtil.NON_NUCLEOTIDE.matcher(sequence).find()) {
  		return false;
  		/*
  		 * System.out.format("I found the text starting at " +
  		 * "index %d and ending at index %d.%n", nonDNAmatcher .start(),
  		 * nonDNAmatcher.end());
  		 */
  	}
  	final Matcher DNAmatcher = SequenceUtil.NUCLEOTIDE.matcher(sequence);
  	return DNAmatcher.find();
  	}
docs: Ambiguous DNA chars : AGTCRYMKSWHBVDN // differs from protein in only one
  (!) - B char