public boolean isStop(String codon) {
		if (codon.length() == 3) return stopCodons.contains(codon.toUpperCase());

		for (int i = 0; i < codon.length(); i += 3) {
			int max = Math.min(codon.length(), i + 3);
			String codonSigle = codon.substring(i, max);
			if (stopCodons.contains(codonSigle.toUpperCase())) return true;
		}

		return false;
	}