I was digging around in the back pages and came across mention of a queen with peppershot brood pattern. This is where a queen lays a comb full of eggs yet when they are capped, some ratio from none up to 50% of the cells are empty.
Lets presume that we are dealing with a sex allele issue, not any of the various diseases.
In simplest terms, a queen lays an unfertilized egg and a drone is produced. If she lays a fertilized egg, then normally, a worker is produced. If she happens to lay an egg with both the sex alleles alike, a diploid drone hatches. The bees don't normally tolerate diploid drones so they destroy the larvae.
Why would a queen lay a diploid drone egg? Part of the problem is that there are only @15 different sex alleles (only about 12 found in the U.S.). It has been proven that the queen typically mates with an average of 17 drones. Since the number of sex alleles is limited, the probability she will mate with a drone carrying a duplicate of her own allele runs about 100%. The result is a queen that lays 1 in 12 eggs as a diploid drone.
I won't cover the statistics involved except to say that some of the sex alleles are present in higher concentrations in the bee population as a whole and if you happen to raise queens with these particular alleles, you will get more peppershot brood patterns.
How do you avoid this problem? Its not entirely possible to avoid and for most purposes is ignored by the average beekeeper. One of the development criteria of the Starline queens was to avoid the diploid issue by carefully arranging mating so that the drones were guaranteed to have different sex alleles than the queens being mated.
The question I would like to see answered is "What can the average beekeeper do to reduce the number of diploids in queens he raises?" I have my own thoughts, what are yours?