Prenatal diagnosis of 5p-.

With the combination of the various banding techniques (G,Q, and R), a small deletion of the short arm of a No.5 chromosome was detected prenatally in the pregnancy of a 39-year-old woman. The deletion appeared to be either intersitial in nature, involving part of p13 and p14, or the result of a translocation with deletion of p13 leads to pter. Both parents were found to have a normal chromosome constitution with normal banding patterns. Thus, this deletion was a de novo event. Repeat amniotic fluid cell chromosome analysis at the time of elective abortion, and postmortem examination of the fetus confirmed the prenatal cytogenetic diagnosis. We wish to emphasize that precise identification of a small deletion, as in this case, requires a combination of the various banding techniques.