The one that causes allergy to meat is ALPHA-GAL , but the nickname, short for galactose-alpha-1, 3-galactose, is a sugar molecule that might just cause you to become allergic to meat.
The sugar molecule is spread from the Lone Star tick bite, named for the Texas-shaped marking on its back. Once bitten by a Lone Star tick, the body's immune system is rewired.
"You're walking through the woods, and that tick has had a meal of cow blood or mammal blood," explained Cosby Stone, an allergy and immunology fellow at Vanderbilt University. "The tick, carrying Alpha-Gal, bites you and activates your allergy immune system."
From this, your body creates Alpha-Gal antibodies and, from that point on, the body is wired to fight Alpha-Gal sugar molecules. The majority of people who develop Alpha-Gal allergy syndrome realize their illness after eating meat, which is rife with Alpha-Gal. The sugar is also present in some medications that use gelatins as stabilizers.
You can find more on google about alpha-Gal. I think is the one Pico has .