A recent series of observations has suggested a linkbetween in vitro fertilization (IVF) and
imprinting disorders, such as Beckwith-Wiedemann syndrome (BWS [MIM 130650]) and
Angelman syndrome (MIM 105830). BWS is a model imprinting disorder and is
characterized by prenatal and/or postnatal overgrowth, macroglossia, abdominal-wall
defects, neonatal hypoglycemia, hemihypertrophy, ear abnormalities, and an increased risk
of embryonal tumors (DeBaun et al.

Recent studies have indicated a link between in vitro fertilization (IVF) and imprinting
disorders that are associated with an increased risk of childhood tumours. In this case–
control study, Halliday and colleagues found that in the IVF population they assessed, the
risk of having a child with Beckwith–Wiedemann syndrome (BWS) was nine times greater
than in the general population. Interestingly, IVF BWS patients consistently show
hypomethylation of the KVDMR1/LIT1 locus, compared with~ 46% of all BWS cases. This …