Expression of imprinted genes among couples with unexplained infertility

Implantation is a result of the complicated and sophisticated interaction between the human embryo and the uterine endometrium. Diverse cellular mechanisms interfere with this interaction. These various mechanisms are governed by different genes. Imprinted genes are thought to play an important role in implantation. H19 and IGF-2 are two imprinted genes which have been extensively studied. These genes are thought to take place during implantation as they remain to be expressed in uterine endometrium although their expression is scanty in most tissues during postnatal life and their expression is strictly dependent on the menstruel cycle and peaks during the time period of luteal phase consistent with the ?implantation window?. Besides, these genes have been previously shown to be important fort he fetal part of the implantation. However, their importance for the endometrial part of the implantation has not been researched in the literature up to now.Based upon this finding, this study aimed to compare expressions of H19 and IGF-2 in endometrial tissue of women with unexplained infertility and in endometrial tissue of women with no fertility problem. A study comparing endometrial expressions of H19 and IGF-2 in women with unexplained infertility and in women with no fertility problem has not been performed till now. In this first study, we aimed to bring a new sight to the underlying factors of unexplained infertility and to trigger new developments in this field.mRNA expression of the gene H19 was 4 times less among women with unexplained infertility as compared to the women with no fertility problem (rate of expression=0.237). This decrease in mRNA expression in the group of women with unexplained infertility was found to be statistically significant (p=0.0001). Comparison of both groups with regard to the expression of IGF-2 also revealed a stasitically significant difference (p=0.015). mRNA expression of IGF-2 was 1.5 times more in the group with unexplained infertility as compared with the control group.This study demonstrated a significantly less expression of maternally expressed H19 and a significantly more expression of paternally expressed IGF-2 in women with unexplained infertility as compared with the control group. This significant difference in the expression of these two imprinted genes important for the implantation between women with unexplained infertility and women with no fertility problem pointed to a possible genetic basis for unexplained infertility.