As I have posted before and here, Ray had his DNA tested. I haven't covered the information on Disease Risk. It isn't explained if the increased or decreased risk factors are from the maternal or paternal side. Most of his risk factors were not significantly higher or lower than the general population except for Celiac Disease. The risk factor in the general population is 0.1% but Ray's DNA shows a risk factor of 2.5% or a 21.32% greater risk when compared to the average. We don't know of any cases in Ray's brothers.
From the 23 and Me website: Celiac Disease is an autoimmune condition triggered by proteins found in wheat, barley, and rye—collectively called "gluten". When someone with Celiac Disease eats gluten, his or her immune system is activated and mounts an attack on the tissue of the small intestine. Symptoms include diarrhea and abdominal pain, but many people with Celiac Disease do not show any overt symptoms. About 1% of the global population is affected by Celiac Disease (approximately 2 million people in the United States). Celiac Disease can strike at any age. Like many other autoimmune diseases, the condition is two to three times more common in women than men. The only treatment for Celiac Disease is adherence to a completely gluten-free diet. Luckily, this completely alleviates symptoms for most people with the disease and allows the damage in their intestines to heal.
I discussed this with my doctor and he stated that it isn't a new disease, but rather one that probably always existed but people didn't know what was causing the symptoms.