Edwards Syndrome (Trisomy 18) [Q91]
Dipl.-Biol. Uwe Heinrich
The Edwards syndrome, arising from a trisomy 18, has an average incidence of 1:3,000 newborns. 80% of the patients exhibit a free trisomy, 10% a mosaic trisomy and another 10% an unbalanced translocation. With 75% of all patients being females, there is a clear gynaecotropism. Physical signs vary; they include dolichocephaly with prominent occiput and small face, dysplastic ears, microcephaly, microretrognathia as well as a prominent calcaneus. Especially in newborns, overlapping of the 3rd and 4th finger by the 2nd and 5th finger is characteristic. Futhermore, cardiac defects, horseshoe kidney, muscle hypertonia and joint contractures can be found. The psychomotor development is considerably delayed. Death usually occurs within the first few months of life, in 90% of all cases within the first year. As in all other autosomal trisomies, a maternal age effect can be observed.