However, visual examination of the methylation state across the entire ICR revealed a region of Cd-associated hypermethylation in both newborn cord blood and maternal blood that overlapped the binding site of RNA pol II at the KCNQ1OT1
promoter (Figure 2B).
Several studies have previously tested the status of imprinted genes in hESCs, suggesting that SNRPN, IPW, and KCNQ1OT1
were highly stable and insensitive to epigenetic perturbations.
The H19 (103280), ICR1 (616186), and KCNQ1OT1
(604115) are located at 11p15.5; and the CDKN1C (60856) is located at 11p54 [1, 7, 8].
The genes encoded at this locus include the genes IGF-R1, CDKN1c, and non-coding RNAs KCNQ1OT1
Among many lncRNAs with such function, several have been characterized, including Kcnq1ot1
, TARID, H19, AS1DHRS4, and DACOR1.
and HI-LNC45, which were previously genetically associated with T2DM , are significantly dysregulated in diabetes islets .
Vitrification at the germinal vesicle stage does not affect the methylation profile of H19 and KCNQ1OT1
imprinting centers in human oocytes subsequently matured in vitro .
These include cytogenetic abnormalities, genetic abnormalities [11p 15 [11, 12] paternal uniparental disomy (UPD), mutations in the CDKN1C gene], epigenetic abnormalities [H19 gene, KCNQ1OT1
gene & microdeletions within IC1 or IC2.
As a proof of principle, the authors correctly detected trisomy 21 by assessing the methylation density of chromosome 21 and correctly deduced the imprinting status of 4 selected loci: H19  [H19, imprinted maternally expressed transcript (non-protein coding)], KCNQ1OT1
[KCNQ1 opposite strand/antisense transcript 1 (non-protein coding)], MEST (mesoderm specific transcript), and GNAS (GNAS complex locus).
Perdeaux et al., "The long noncoding RNA Kcnq1ot1
organises a lineage-specific nuclear domain for epigenetic gene silencing," Development, vol.
ZAC, LIT1 (KCNQ1OT1
) and [p57.sup.KIP2] (CDKN1C) are in an imprinted gene network that may play a role in Beckwith-Wiedemann syndrome.
The syndrome is associated with alterations in 2 distinct imprinting domains on 11p15: a telomeric domain containing the H19 and IGF2 genes and a centromeric domain including the KCNQ1OT1
and CDKNIC genes.