How sensitive are polygenic risk scores (PRS scores) to small changes in coefficients [or just changing the population you study]

Like, Levine’s regressions (not PRS, but w/e) often have drastically different coefficient values depending on dataset [and due to interaction effects, assigning high coefficient to one value often decreases coefficients on other values if you compare some regressions w/each other]

There are PRS scores on intelligence (the new thiel fellow genome sequencing startup tries this) and longevity [anton kulaga and olga have their own longevity PRS models and they give you a t-shirt showing your longevity PRS but I suspect this is highly underdeveloped]

https://x.com/hsu_steve/status/1811857144708251832