ORIGINAL PAPER Human EGFR, a candidate gene for the Silver-Russell syndrome, is biallelically expressed in a wide range of fetal tissues Emma L Wakeling 1,2 , Sayeda N Abu-Amero 1 , Philip Stanier 1 , Michael A Preece 1,2 and Gudrun E Moore 1 1 A ction Research L aboratory for the Molecular Biology of Fetal Development, Division of Paediatrics, Obstetrics and Gynaecology, Imperial College School of Medicine, Queen Charlotte’s and Chelsea Hospital, London, UK 2 Institute of Child Health, University of London, UK Maternal uniparental disomy of chromosome 7 (mUPD7) has been reported in around 10% of cases of Silver-Russell syndrome (SRS). This suggests that at least one gene on chromosome 7 is imprinted and involved in the pathogenesis of this condition. One candidate is epidermal growth factor receptor ( EGFR) which maps to chromosome 7p12, a region homologous to an imprinted region on mouse chromosome 11. Using a restriction fragment length polymorphism, biallelic expression of EGFR was found in a range of normal human fetal tissues. Expression was also demonstrated in fibroblasts and lymphoblasts from SRS patients with mUPD7. Thus no evidence that EGFR is imprinted was found, making its involvement in SRS unlikely. However, EGFR was shown to be widely expressed in the human fetus, evidence that this gene plays an important role in early development. Keywords: epidermal growth factor receptor; Silver-Russell syndrome; maternal uniparental disomy; imprinting; fetal expression Introduction Maternal uniparental disomy for chromosome 7 (mUPD7) has been described in several patients with intrauterine growth retardation (IUGR). 1–3 More recently, approximately 10% of cases of Silver-Russell syndrome (SRS) have also been found to be associated with mUPD7. 4,5 SRS is characterised by intrauterine and postnatal growth retardation with relative sparing of cranial growth, triangular facies and downturned corners of the mouth. In a large proportion fifth finger clinodactyly and facial, limb or truncal asymmetry is also present. In five SRS patients with mUPD7 studied by our group, no consistently isodisomic areas have been found (unpublished observation). This makes exposure of a recessive gene an unlikely explanation for the phenotype associated with mUPD7, suggesting instead that one or more gene(s) on chromosome 7 are imprinted and play a role in the pathogenesis of SRS and IUGR in some cases. Likely imprinted candidate genes can be sought by comparison of mouse and human linkage maps. Several Correspondence: Dr E Wakeling, Action Research Labo- ratory for the Molecular Biology of Fetal Development, Division of Paediatrics, Obstetrics and Gynaecology, Imperial College School of Medicine, Queen Charlotte’s and Chelsea Hospital, Goldhawk Road, London W6 0XG, UK. Fax: +44 181 383 1838; Tel: + 44 181 383 3533; E-mail: e.wakeling@rpms.ac.uk Received 30 January 1997; revised 6 October 1997; accepted 24 November 1997 Journal: European Journal of Human Genetics Article: 5200179 European Journal of Human Genetics (1998) 6, 158–164 © 1998 Stockton Press All rights reserved 1018–4813/98 $12.00 http://www.stockton-press.co.uk/ejhg