// Check MNPs vs. CHets:
if (containsRefAllele(site1Alleles) && containsRefAllele(site2Alleles)) {
logger.debug("HET-HET for " + samp + " at " + GATKVariantContextUtils.getLocation(genomeLocParser, vc1) + ", " + GATKVariantContextUtils.getLocation(genomeLocParser, vc2));
if (logger.isDebugEnabled() && !(gt1.isHet() && gt2.isHet()))
throw new ReviewedGATKException("Since !gt1.isHomRef() && !gt2.isHomRef(), yet both have ref alleles, they BOTH must be hets!");
// There's the potential to only have REF-ALT, ALT-REF (CHet), or possibly ALT-ALT together (MNP)
boolean hasMNP = false;
all2It = site2Alleles.iterator();