Subtle familial unbalanced translocation t(8;11)(p23.2;p15.5) in two fetuses with Beckwith-Wiedemann features

We describe a subtle translocation t(8;11)(p23.2;p15.5) ascertained after t wo induced abortions in the same sibship because of the discovery of fetal hydrops on ultrasound examination. Initial cytogenetic studies performed on cultured amniotic fluid cells were considered as normal in both fetuses. H igh resolution banding analysis and FISH studies performed on the parents' chromosomes revealed a paternal translocation t(8;11)(p23.2;p15.5). Retrosp ective FISH analysis of both fetuses showed that they carried the same chro mosomal imbalance including a distal monosomy 8pter and a distal trisomy 11 pter. The phenotypes of the fetuses were re-examined and found to be compat ible with Beckwith-Wiedemann syndromes (BWS). FISH analysis using an IGF2 p robe demonstrated the presence of three copies of the IGF2 gene. This study highlights the value of searching for subtle chromosome rearrangements in families with recurrent unexplained multiple malformation syndromes discove red prenatally. Also, it contributes to a better delineation of the prenata l phenotype of BWS. Finally, it sheds new light on the aetiology of nonimmu ne hydrops fetalis. Copyright (C) 2000 John Wiley & Sons, Ltd.