Silver-Russell syndrome (SRS) (OMIM #180860), another infrequent imprinting disorder, results from a microdeletion in the chromosomal 11p15.5 region, maternal uniparental disomy (mUPD) of chromosome 7, mutations in the maternally imprinted IGF-2 gene, or other rare molecular abnormalities. The gene discussed is IGF2; the disease is Silver-Russell syndrome.