Talking specifically about celiac disease, not non-celiac gluten sensitivity, 4 out of 5 people who have celiac disease are not diagnosed with it. If your brot

Talking specifically about celiac disease, not non-celiac gluten sensitivity, 4 out of 5 people who have celiac disease are not diagnosed with it. If your brother has it, there's a 1 in 10 chance you do too.