Identification of interstitial maternal uniparental disomy (UPD) (14) and complete maternal UPD(20) in a cohort of growth retarded patients

The association of uniparental disomy (UPD) and short stature has been reported for different chromosomes and in several conditions. Therefore, we investigated a cohort of 21 patients referred because of intrauterine and postnatal growth retardation for UPD of chromosomes 2, 7, 9, 14, 16, and 20. Typing of short tandem repeats showed maternal UPD(14) and maternal UPD(20) in two cases. In the first case, an interstitial UPD(14) was detected and the growth retarded newborn showed some additional clinical signs in common with the putative "maternal UPD(14) syndrome". The maternal UPD(20) patient showed minor features. However, since it is only the second maternal UPD(20) case it is too early to delineate a specific syndrome and the role of this constitution in growth remains to be investigated. Our data suggest that searching for UPD in growth retarded patients is a helpful approach to getting more information on the role of UPD in growth retardation. Based on our results, general considerations and indications for UPD testing are discussed.