The pregnancies and deliveries of buprenorphine-using women were uneventful, but severe NAS and need for morphine replacement therapy was seen in 57% of the buprenorphine-exposed newborns. A high number of sudden infant deaths occurred.
There is a substantial risk of children born to mothers with significant alcohol and/or substance abuse related problems for out-of-home care during early childhood. Factors identified during the pre- and perinatal period are associated with this risk.
Study Question
Does prenatal alcohol exposure (PAE) affect regulation of the
insulin-like growth factor 2 (IGF2)/H19
locus in placenta and the growth-restricted phenotype of newborns?
Summary Answer
PAE results in genotype-specific trends in both placental DNA methylation at the
IGF2/H19
locus and head circumference (HC) of newborns.
What is Known Already
PAE can disturb development of the nervous system and lead to restricted growth of the head, even microcephaly. To clarify the etiology of alcohol-induced growth restriction, we focused on the imprinted
IGF2/H19
locus known to be important for normal placental and embryonic growth. The expression of
IGF2
and a negative growth controller
H19
are regulated by the
H19
imprinting control region (
H19
ICR) with seven-binding sites for the methylation-sensitive zinc-finger regulatory protein CTCF. A single nucleotide polymorphism rs10732516 G/A in the sixth-binding site has shown to associate with genotype-specific DNA methylation profiles at the
H19
ICR.
Study Design, Size, Duration
By grouping 39 alcohol-exposed and 100 control samples according to rs10732516 polymorphism we explored alcohol-induced, genotype-specific changes in DNA methylation at the
H19
ICR and the promoter region of
H19
(
H19
differentially methylated region). Also,
IGF2
and
H19
mRNA expression level in placenta as well as the phenotypes of newborns were examined.
Participants/Materials, Setting, Methods
We explored alcohol-induced, genotype-specific changes in placental DNA methylation by MassARRAY EpiTYPER and allele-specific changes by bisulphite sequencing.
IGF2
and
H19
expression in placenta were analyzed by quantitative PCR and the HC, birthweight and birth length of newborns were examined using national growth charts.
Main Results and the Role of Chance
We observed a consistent trend in genotype-specific changes in DNA methylation at
H19
ICR in alcohol-exposed placentas. DNA methylation level in the normally highly methylated paternal allele of rs10732516 paternal A/maternal G genotype was decreased in alcohol-exposed placentas. In addition to decreased
IGF2
mRNA expression in alcohol-exposed placentas of this specific genotype (
P
= 0.03), we observed significantly increased expression of
H19
in relation to
IGF2
when comparing all alcohol-exposed placentas to unexposed controls (
...
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.