A Female Newborn Having Mosaicism with Near-Tetraploidy and Trisomy 18

摘要

Tetraploidy is characterized by the presence of four complete sets of chromosomes in an individual. Full tetraploidy is usually considered lethal. To date, only ten live-births with the condition have been reported. Trisomy 18 without neonatal intensive treatment is also known to be fatal. We report a female newborn who had mosaicism with near-tetraploidy and trisomy 18 (94, XXXX, +18, +18/47, XX, +18). She had features of conditions. The most plausible mechanism of the formation was a failure of cytoplasmic cleavage at the first division of the zygote. The longer survival of the patient compared with the 10 previously reported live-births with non-mosaic tetraploidy may be due to the dominance of the trisomy cells. We suggest that non-tetraploid cells, even when trisomic for chromosome 18, might contribute to longer survival in comparison to non-mosaic tetrapolid patients. (C) 2016 Wiley Periodicals, Inc.