Clinical and molecular findings in two patients with Russell-Silver syndrome and UPD7: Comparison with non-UPD7 cases

The clinical presentation of prenatal and postnatal growth deficiency, tria ngular face, relative macrocephaly, and body asymmetry is frequently diagno sed as Russell-Silver syndrome (RSS). Materna; uniparental disomy (UPD) of chromosome 7 was reported previously in a small subset of individuals with RSS phenotype or primordial growth retardation. The primary purpose of this study was to identify RSS patients with UPD7 and determine whether or not they present phenotypic findings that distinguish them from RSS patients wi thout UPD7. UPD7 testing was performed in 40 patients with unexplained grow th retardation, including 21 patients with a diagnosis of RSS. In addition, a subset of patients was screened with markers spanning chromosome 7 to de tect potential microdeletions or segmental uniparental disomy. Two of the R SS cases were identified to have maternal UPD7; no cases with deletion or p artial UPD were detected. Together with previously published studies, UPD7 was identified in 11/120 (9%) of individuals with classical RSS phenotype. Our patients with UPD7 and those previously published had a classical RSS p henotype and were not clinically distinguishable from other children diagno sed with RSS. Am. J. Med. Genet. 87:230-236, 1999. (C) 1999 Wiley-Liss, Inc .