Transient neonatal diabetes (TND) is a rare form on diabetes which appears shortly after birth and
disappears by 18 months. Several cases of transient neonatal diabetes exhibit paternal uniparental
disomy (UPD) of chromosome 6 (Temple
IK, et al. 1995). Additionally, paternal UPD has been associated with agenesis of pancreatic
beta cells and neonatal diabetes (Abramowicz
MJ, et al. 1994). A genotypic study of 30 TND patients showed that 11 patients had paternal UPD
of chromosome 6, 11 had a duplication of 6q24 (containing the TND critical region) which was
paternal in origin when tested (9/11), one patient had loss of maternal methylation of a CpG island
within the TND critical region and 7 had no apparent chromosome abnormalities (Temple
IK, et al. 2000).
A case showing hemizygous deletion of unknown parental origin has been reported (Diatloff-Zito
et al, 2007).
The TND critical region is within a 3-400 kb region in 6q24, between D6S308 (AFM262XE9)
and D6S1010 (CHLC.GATA41E03)
and differential methylation has been identified (Gardner
RJ, et al. 2000; Cave
H, et al. 2000). A study by Arima
T, et al. 2001 showed 5 of 6 TND cases showed loss of maternal methylation in a differentially
methylated region, a putative imprinting control region which overlaps ZAC
Loss of imprinting of ZAC and HYMAI has been reported in a patient with TND (Mackay
G, et al. 2002).