In the article by Sommer entitled “Single-Tube Polymerase Chain Reaction for Rapid Diagnosis of the Inversion Hotspot for Mutation in Hemophilia A,” (Blood 92:1458-1459), a correction should be noted. In order for the assay to be reproduced, two errors must be corrected. The correct sequence of the “B” primer should be 5′ CCC CAA ACT ATA ACC AGC ACC TTG AAC TTC CCC TCT CAT A 3′. The concentration unit of the dNTPs should be micromolar.