public static double[][] getMarkerAlleleTotals(List<Accession> accessions) {
	if (accessions.size()==0) return null;

	Accession a1 = accessions.get(0);
	int markerCnt = a1.numSSRMarkers();
	double markerAlleleTotals[][] = new double[markerCnt][];

	ListIterator<List<Double>> mItr = a1.getSSRValues().listIterator();
	ListIterator<Double> aItr = null;

	int i = 0;
	while (mItr.hasNext()) {
	    List<Double> alleles = mItr.next();

	    markerAlleleTotals[i] = new double[alleles.size()];
	    for(int j=0; j<alleles.size(); j++) {
		markerAlleleTotals[i][j] = 0.0;
	    }
	    i++;
	}
	
	for(Accession a : accessions) {
	    mItr = a.getSSRValues().listIterator();
	    aItr = null;

	    i = 0;
	    while (mItr.hasNext()) {
		aItr = mItr.next().listIterator();
		int j = 0;
		while (aItr.hasNext()) {
		    Double val = aItr.next();
		    if(val != null) {
			double v = val.doubleValue();
			markerAlleleTotals[i][j] += v;
		    }
		    j++;
		}
		i++;
	    }
	}

	return markerAlleleTotals;
    }