S a successful approach for infertile couples, which commonly overcomes the
S a successful approach for infertile couples, which commonly overcomes the underlying infertility causes resulting in significantly PubMed ID:https://www.ncbi.nlm.nih.gov/pubmed/28298493 higher pregnancy PubMed ID:https://www.ncbi.nlm.nih.gov/pubmed/27872238 rates compared to natural conception. The variability in patient characteristics is directly related to the response to ART treatment, which consequently dictates the need* Correspondence: [email protected] Division of Human Reproduction, IVF Unit, 1st Department of Obstetrics and Gynaecology, Thonzonium (bromide) solubility Alexandra Hospital, Athens University Medical School, Athens, Greecefor reliable, personalized diagnostic and therapeutic approaches to optimize efficacy, as well as safety outcomes. Significant scientific discoveries have made the causes of infertility more apprehensible and ART has facilitated the development of increasingly complex diagnostic tools, prognostic models and treatment options. As a result, it is crucial to extend investigation to more genetic factors, not necessarily related directly to the reproductive system, such as runt-related transcription factor 2 (RUNX2) gene, in order to conclude whether or not they are involved in the outcome of ART treatment [1].?2012 Papamentzelopoulou et al.; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Papamentzelopoulou et al. Reproductive Biology and Endocrinology 2012, 10:99 http://www.rbej.com/content/10/1/Page 2 ofRUNX2 (Cbfa1, AML-3, PEBP2A) is well known for regulating both intramembranous and endochondral bone formation, as well as osteoblast development and differentiation and chondrocyte differentiation. It is a member of the runt family of transcription factors. The three mammalian RUNX proteins (RUNX1, RUNX2, RUNX3) share a highly conserved 128 amino acid DNA binding domain [2]. RUNX2 gene is located on chromosome 6, consists of eight coding exons and spans a genomic region of 130 kb. It contains a DNA-binding domain, a region of glutamine and alanine repeats in the N-terminal region and a region rich in proline-serinethreonine, which is necessary for transcriptional activation of target genes [3]. Moreover, RUNX2 association with the nuclear domain facilitates interaction with many co-regulatory proteins and chromatin-modifying complexes for the regulation of gene transcription [4]. In general, RUNX2 has been shown to play a crucial role in cell differentiation. Its expression has been recently identified in the rat ovary, but little is known about the regulatory mechanism of RUNX2 expression and the specific function of this protein in the human ovary. RUNX2 mRNA levels were shown to be increased by the luteinizing hormone (LH) surge in preovulatory follicles and newly forming corpus luteum in women and rodents, as determined by real time PCR, in situ hybridization, and human microarray analyses [5,6]. As a result, the LH-surge induced RUNX2 is functionally linked to various aspects of luteal development by regulating the expression of luteal specific genes. Moreover, in a model of doxycyline-inducible, triple transgenic mice (CMV-Cre;ROSA26 neoflox/+ – rtTA;Tet-ORUNX2) highly induced RUNX2 transgene expression was observed in the ovary [7]. A recent study confirmed the strong association of RUNX2 gene with ovulation, luteinization and steroidogenesis, since RUNX2 was down-regulated in gr.