No evidence of uniparental disomy 2, 6, 14, 16, 20, and 22 as a major cause of intrauterine growth retardation

Intrauterine growth retardation (IUGR) is defined as length and/or weight b elow the 10th percentile. Etiology and, consequently, long-term outcome are extremely heterogeneous with chromosomal abnormalities found in up to 7%. Recently, uniparental disomy (UPD), i.e. the inheritance of both homologues of one pair of chromosomes from only one parent, was found in an increasin g number of children with IUGR. Particularly, UPD of chromosome 7 was found in up to 10% of patients with IUGR and/or a phenotype of primordial growth retardation or Silver-Russell syndrome (SRS), but also UPD of chromosomes 2, 6, 14, 16, 20, and 22 was reported in single cases with IUGR. To evaluat e impact and relevance of UPD in children with IUGR we investigated 23 spor adic cases with IUGR subsequently diagnosed as primordial growth retardatio n (n = 13) or SRS (n = 10) by molecular methods for UPD of chromosomes 2, 6 , 14, 16, 20, and 22. No instance of UPD was found. Inheritance of all chro mosomes investigated was biparental in all cases. Therefore, we conclude th at UPD of these chromosomes is not a major cause of IUGR.