Molecular Evaluation of Children with Clinical Russell-Silver Phenotypes: The First Report From Iran

Russell-Silver syndrome is a rare heterogeneous genetic disorder that is mostly known because of its prenatal and postnatal growth retardation. Patients with Russell-Silver syndrome have syndromic facial appearance, as well as some other common clinical features. Disrupted methylation of 11p15 is the most common genetic abnormality that is seen in these patients, called as one of the tire molecular studies in diagnostic guidelines. In the present study, the methylation status of 11p15 was evaluated in a group of children with clinical diagnosis of Russell-Silver syndrome in Iran. A total number of 15 children with a clinical diagnosis of Russell-Silver syndrome were enrolled in this descriptive study. Children’s DNA was extracted by the salting-out method and the 11p15 region was assessed by the methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA) method. The correlation of molecular results was then evaluated with clinical features. The mean age of children was 4.5 years and most of them were male. Among 15 children, four children had a confirmed molecular diagnosis of Russell-Silver syndrome according to the MS-MLPA results. All of these four patients had low set ears, high peach voice, micrognathia, failure to gain weight, growth failure, and triangular face. Less than one-third (26.6 %) of our patients had confirmed Russell-Silver syndrome by the MLPA analysis. This experiment showed that Russell-Silver syndrome with abnormal 11p15 methylation was less frequent in our population and showed similar clinical findings in comparison with other studies.