Do all twins with a balding gene lose hair at the same time? Is it possible for one twin to not have the balding gene? Or is it possible for one twin to bald at a different rate if they were at a different stress level ?
We have seen many identical twins (same genes) over our 23 years at NHI but they do not bald or lose hair at the same time. Maybe several months to years apart. This may suggest some outside influence. For example one set of twins twin used anabolic steroid and lost his hair fast while his twin did not. Another twin used a hair piece and developed traction alopecia from the tapes and glues. The twin with more hair, at one point, was a donor for his brother who needed the extra hair.
I have seen twins without hair loss, but have not followed one of a pair with hair loss. I would imagine that stress might cause one twin to have accelerated hair loss if they had the genes for balding.