SYSTEMATIC SEARCH FOR UNIPARENTAL DISOMY IN EARLY FETAL LOSSES - THE RESULTS AND A REVIEW OF THE LITERATURE

About 20% of all human conceptuses are estimated to be trisomic and tr isomy of all chromosomes remains a common cause of early fetal loss, U niparental disomy (UPD) has been reported for most human chromosomes a nd may be an underrecognized contributor to embryonic lethality, To in vestigate the contribution of UPD to spontaneous abortions, we devised a genome-based screening strategy to identify holochromosomic UPD in 18 fetal losses. No cases of UPD were identified using this approach. Based on our data, UPD does not appear to be a significant contributor to early embryonic lethality. The results of the study are presented along with a review of the cases of UPD reported in the literature by chromosome, parental origin, mode of ascertainment, and phenotypic con sequences due to imprinting. Am. J, Med. Genet. 79:366-372, 1998. (C) 1998 Wiley-Liss, Inc.