From time to time I drink a lot, is it true that alcohol can destroy my DNA?
Drinking alcohol increases the chances of some cancers, so that would make it true, as cancers appear as a result of mutations in cells.
Genetics may play a role. Certain ethnic groups (see the flush that many East Asians experience) can’t handle alcohol as well as others. Mostly because they lack the enzymes necessary for breaking down the acetaldehyde into acetate.