An increase of chromosomal abnormalities was found in leukocytes of LSD users compared to drug-free controls. Elevated breakage rates were also found in children exposed to the drug in utero. The data showed no correlation between amount of drug per dose, number of doses, or total dosage and frequency of chromosomal breaks.
Egozcue J, Irwin S, Maruffo CA. Chromosomal Damage in LSD Users. JAMA. 1968;204(3):214-218. doi:10.1001/jama.1968.03140160024006