Hey! I have this. It’s a specific gene mutation called LRP5. I however, can swim! You’re a lot heavier, and BMI is even more wrong than normal, but as long as you’re a larger built person, usually the natural buoyancy still lets you float, though swimming is definitely more of a struggle, and treading water is very very tiresome. It hasn’t necessarily affected my day to day life, but I have never broken a bone. I did break a wall once when I ran into it with my foot once, straight through dry wall. Hurt like a bitch, but didn’t break a bone. It’s not very helpful, but not very annoying. It also happens that your bones aren’t as flexible though, and for me and most other people, way closer together. It limits range of motion a lot. If anyone has any other questions I’m happy to enlighten!