Alcohol Never Burned My Throat

So, when I was 15, I took my first ever shot of 40% vodka. It didn’t really burn. I just straight-faced it. It kinda scared my older brother lol. Alcohol has never really burned my throat, unless its above 60% alcohol. Drinks under 25% just go down like water or lemonade. Is this genetic? Or is it just good/bad luck?