void addIfDiff(char codonOld[], char codonNew[]) {
		String cold = new String(codonOld);
		String cnew = new String(codonNew);
		if (!cold.equals(cnew)) {
			codonsOld += transcript.isStrandPlus() ? cold : GprSeq.wc(cold);
			codonsNew += transcript.isStrandPlus() ? cnew : GprSeq.wc(cnew);
		}
	}