The three main characteristics of this condition are:
- High birth weight
- Large tongue
- Umbilical hernia or exomphalos (The guts protrude through the abdominal wall in a sack)
People may also have:
- Low blood sugar
- Asymmetric growth (one side of the body bigger than the other)
- Tall stature
- Enlarged kidneys
- Increased risk of childhood kidney tumour (Wilms tumour)
Genetic Causes
This condition is due to altered expression of imprinted genes on chromosome 11. The most common causes are loss of methylation causing over expression of a growth repressor molecule called CDKN1C (50% of cases), or paternal UPD of chromosome 11 in a proportion of cells (approximately 20%) or too much methylation (hypermethylation) causing over expression of the growth factor IGF2 (approximately 5%). Some cases are inherited through the generations either because of mutations in the gene CDKN1C or chromosome rearrangements involving chromosome 11.
Useful Links
http://www.ncbi.nlm.nih.gov/books/NBK1394/ - GeneReviews
References
- Tan, T. Y. and D. J. Amor. "Tumour surveillance in Beckwith-Wiedemann syndrome and hemihyperplasia: a critical review of the evidence and suggested guidelines for local practice." J.Paediatr.Child Health 42.9 (2006): 486-90.
- Weksberg, R., C. Shuman, and J. B. Beckwith. "Beckwith-Wiedemann syndrome." Eur.J.Hum.Genet. 18.1 (2010): 8-14.
- Cooper, W. N., et al. "Molecular subtypes and phenotypic expression of Beckwith-Wiedemann syndrome." Eur.J.Hum.Genet. 13.9 (2005): 1025-32.
- Temple IK. Imprinting in human disease with special reference to transient neonatal diabetes and Beckwith-Wiedemann syndrome. Endocr Dev. 2007;12:113-23. Review. PubMed citation