KCNQ1OT1 (the most-often misregulated imprinted gene in BWS) was biallelically-expressed in various organs in two out of seven overgrown conceptuses from the ART group, but shows monoallelic expression in all tissues of the AI conceptuses. Further, other characteristics reported in BWS were observed in the ART group, such as large tongue, umbilical hernia, and ear malformations. Seven of the 27 conceptuses in the ART group were in the > 97th percentile body weight when compared with controls. To test this, Bos taurus indicus × Bos taurus taurus F1 hybrids were generated by artificial insemination (AI control) or by ART. The main goal of our study is to determine if LOS shows similar loss-of-imprinting at loci known to be misregulated in BWS. As in humans, ART can also induce a similar overgrowth syndrome in ruminants which is referred to as large offspring syndrome (LOS).
Children conceived with the use of assisted reproductive technologies (ART) appear to have an increased incidence of BWS. BWS has been associated with misregulation of two clusters of imprinted genes. Beckwith-Wiedemann syndrome (BWS) is a human loss-of-imprinting syndrome primarily characterized by macrosomia, macroglossia, and abdominal wall defects.