Expression of the imprinted IGF2 and H19 genes in the endometrium of cases with unexplained infertility.
OBJECTIVE
As genomic imprinting plays a critical role in the development of the placenta, the aim of this study was to detect whether the expression levels of the imprinted genes IGF2 and H19 in the endometrium differ between infertile and fertile women.


METHODS
Total RNA was extracted from 30 (15 unexplained infertile and 15 fertile) women's endometrial tissue. cDNA was synthesized from total RNAs of each sample. IGF2 and H19 mRNA expression levels were measured quantitatively using the Real Time PCR method. In order to determine the allelic expression of IGF2 and H19, genomic DNA was extracted from endometrial tissues.


RESULTS
When compared with the control group, increased mRNA expression of IGF2 was detected (1.5-fold change, P=0.015) in the unexplained infertility group. In contrast, H19 expression was lower in the infertility group as compared to the control group (4-fold change, P<0.0001). Restriction analysis of cDNA-derived PCR product showed that all patients and controls indicated monoallelic expression of IGF2 and H19.


CONCLUSIONS
Our results showed that altered expression of these imprinted genes might affect implantation and that their timely and appropriate activation is important for proper functioning. To understand the molecular epigenetic basis of implantation and placental development, genomic imprinted genes should be further investigated.
Korucuoglu
Umit
U
Department of Obstetrics and Gynecology, Faculty of Medicine, Gazi University, 06500 Besevler, Ankara, Turkey.
Biri
Aydan Asyali
AA
Konac
Ece
E
Alp
Ebru
E
Onen
Ilke H
IH
Ilhan
Mustafa N
MN
Turkyilmaz
Esengul
E
Erdem
Ahmet
A
Erdem
Mehmet
M
Menevse
Sevda
S
D000328:Adult; D000483:Alleles; D004717:Endometrium / Q000378:metabolism*; D005260:Female; D015870:Gene Expression / Q000235:genetics; D018392:Genomic Imprinting / Q000235:genetics*; D006801:Humans; D007247:Infertility, Female / Q000235:genetics* / Q000378:metabolism; D007335:Insulin-Like Growth Factor II / Q000235:genetics* / Q000378:metabolism; D018579:Patient Selection; D020641:Polymorphism, Single Nucleotide / Q000235:genetics; D062085:RNA, Long Noncoding; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D022661:RNA, Untranslated / Q000235:genetics* / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D018709:Statistics, Nonparametric
C094335:H19 long non-coding RNA; C035170:IGF2 protein, human; D062085:RNA, Long Noncoding; D012333:RNA, Messenger; D022661:RNA, Untranslated; D007335:Insulin-Like Growth Factor II