One paper cited by respondent, O'Roak, suggests that the the vast majority of mutations found in ASD occur pre-conception, in the sperm of the father. Dr. Arking also cites the Iossifov et al.161 paper to assist his belief that de novo mutations affiliated with ASD come about prenatally. Dr. Arking stated why these barcoding research do not assistance Dr. Deisher's hypothesis.