DNA methylation analysis at imprinted locus and global methylation in spermatozoa of normozoospermic individuals of idiopathic Recurrent Spontaneous Miscarriage

Background Gametic imprint marks play an essential role in dictating the expression profile to the developing embryo as they are faithfully inherited in the somatic tissues. Insulin-like growth factor(IGF2) is a mitogen and IGF2-H19 locus, a paternally imprinted locus, has been found to be associated with embryo loss in numerous publications. Aberrations in its methylation levels in tamoxifen treated rats evidenced despite any change in sperm parameters [1]. DLK1(Drosophila-like homologue1) is also involved in embryogenesis and the IGDMR(a paternally methylated locus) methylation aberrations has been found to be associated in oligozoospermic patients [2]. Recurrent Spontaneous Miscarriage (RSM) is the spontaneous consecutive loss of >3 pregnancies in the first trimester. Although many factors have been attributed to its cause many cases remain idiopathic and undiagnosed. Based on evidences supporting the prevalence of paternal epigenetic marks associating with embryo loss we hypothesized the involvement of aberrant methylation of imprinted genes IGF2H19 imprint control region, DLK1-GTL2 IGDMR and global methylation in spermatozoa of idiopathic Recurrent Spontaneous Miscarriage (RSM) case participants having normozoospermic profile in order to understand its involvement in causing early embryo loss in these cases.