GRB10 and Silver-Russell syndrome: Maternal uniparental disomy of chromosome 7 is present in 5-10% of patients with Silver-Russell syndrome (SRS), and duplication of 7p including <i>GRB10</i> (Growth Factor Receptor-Bound Protein 10), an imprinted gene that affects pre-and postnatal growth retardation, has been associated with the SRS phenotype.