Sounds like the Covid Vaxxines and boosters.
“Symptoms may include shortness of breath and wheezing, repeated infections of the lungs and liver, yellow skin, feeling overly tired (fatigue), rapid heartbeat when standing, vision problems, and weight loss. https://rarediseases.info.nih.gov/diseases/5784/alpha-1-antitrypsin-deficiency“
A better reference is https://medlineplus.gov/genetics/condition/alpha-1-antitrypsin-deficiency/#inheritance.
It’s autosomal inheritance with co-dominance. Generally, people need two “bad” copies of the gene, or one “bad” copy and one “weak” copy, to have any symptoms. Even with two copies of the “bad” gene, most symptoms don’t show up until the 20’s-50’s and can be confused or overshadowed by other diseases of the lungs and liver that hit at that age with certain behaviors (drinking, smoking, drug use). Specifically, constipation is a known complication of chronic opioid use, emphysema of heavy or long-term smoking, and fatigue and jaundice of alcohol and drug abuse with or without hepatitis.
All of these sound like the stereotypical image of the hard-driving rock star, so going with the Willie Sutton school of bank robbing, alpha-1-anti-trypsin deficiency as the problem with Elvis or his progeny seems less likely.
Jus’ sayin’.
COPD is almost always a symptom.