Human EGFR, a candidate gene for the Silver-Russell syndrome, is biallelically expressed in a wide range of fetal tissues

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.