What are the symptoms? Babies with Silver-Russell syndrome have a low birth weight and fail to thrive as infants. Head growth is normal, however, so the head may appear unusually large compared to the rest of the body. Affected children are thin and have poor appetites, and some develop hypoglycaemia (low blood sugar) as a result of feeding difficulties. Other characteristics may include a short incurved fifth finger, triangular facial features, turned down corners of the mouth, café au lait spots (patches of skin that resemble the colour of coffee and milk) and syndactyly (where two or more digits are fused together). Body asymmetry (one side of the body is larger than the other) is common. In a small minority of cases, mild neurological delay can occur. In the first year of life excessive sweating, particularly at night, is common and may be because of chronic hypoglycaemia. This is extremely important to recognise and may well be the cause of the educational difficulties that have been identified in such children. Life expectancy for somebody with Silver-Russell syndrome is normal. What are the causes? Silver-Russell syndrome has a genetic cause; however, the genetics of this condition are complex. The condition often results from the abnormal regulation of certain genes that control growth. Research has focused on genes located in particular regions of chromosome 7 and chromosome 11. However, around 50% of children with Silver-Russell syndrome have no known genetic abnormality. How is it diagnosed? Silver-Russell syndrome is diagnosed clinically (by a doctor or specialist) based on observation of symptoms. Genetic testing may be used to confirm the diagnosis. How is it treated? Continuous overnight feeds using gastric tubes or gastrostomy (creation of an artificial surgical opening into the stomach for nutritional support) may need to be considered to help a baby that is not putting on weight. Hypoglycaemia will need to be monitored and treatment given if it is a continuing problem. Growth hormone may be given to increase growth – a specialist doctor called an endocrinologist will decide if this is necessary. Psychological support may be required to support a person who feels affected by their short stature. For children with learning difficulties additional educational support may be required. Specialist care from paediatric gastroenterology, orthopaedics and orthodontics is also often required. Inheritance patterns and prenatal diagnosis Inheritance patternsMost cases of Silver-Russell syndrome are sporadic, which means they occur in people with no history of the disorder in their family. Less commonly, Silver-Russell syndrome can run in families. In some affected families, the condition appears to have an autosomal dominant pattern of inheritance. It has been suggested that there is a congenital association between siblings which may result from placental insufficiency. Such placental problems may be hereditary. Prenatal diagnosisThere is no specific diagnostic test that can be used during pregnancy, but a series of ultrasound scans starting from early pregnancy will confirm intra-uterine growth is lower than expected. Is there support? Information and support in the UK for Silver-Russell syndrome is provided by the Child Growth Foundation (see entry Restricted Growth).