In 1962, a bull named ‘Chief’ revolutionized the dairy industry forever. The bull produced far more dairy than average, and industry leaders wanted to take full advantage of the situation. They later collected and froze sperm samples from Chief to be distributed around the nation.
These samples then went on to inseminate cows all over the United States with the hope that the secret dairy-producing recipe in Chief’s genetics could be replicated through offspring. From these insemination attempts, Chief ended up with 16,000 daughters, 500,00 granddaughters, and 2 million great-granddaughters.
While these attempts certainly boosted dairy production for the industry, it didn’t come without its adverse side-effects. Chief’s DNA contained a potentially-deadly mutated gene known as APAF1.
Offspring with just one of these genes didn’t cause any trouble, but as Chief’s descendants began interbreeding with one another, some ended up with two of these genes; those that did had died in the womb before birth. Close to 525,000 offspring were impacted by this unfortunate turn of events.