void coverageByExons(Marker read, Marker m, String typeRank) {
		// Find corresponfing transcript
		Transcript tr = (Transcript) m.findParent(Transcript.class);
		if (tr == null) return;

		// Number of exons
		int exons = tr.numChilds();

		// Do we need to add new counters?
		if (coverageByExons.size() <= exons) {
			for (int i = coverageByExons.size(); i <= exons; i++)
				coverageByExons.add(new CoverageByType());
		}

		// Perform stats
		CoverageByType cbe = coverageByExons.get(exons);
		PosStats posStats = cbe.getOrCreate(typeRank);
		posStats.sample(read, m);
	}