//A helper function that gets the parent set of the set of children
private static Set<EffectType> getParentSet(final Set<EffectType> children){
final Set<EffectType> parents=new HashSet<>();
for(EffectType child:children){
final EffectType parent = snpEffectGraph.get(child);
if(parent!=null) parents.add(parent);
}
return parents;
}