ABSTRACT: Background: Children conceived through assisted reproduction are at an increased risk for growth and genomic imprinting disorders, often linked to DNA methylation defects. It has been suggested that assisted reproductive technologies (ART) and the underlying parental infertility can induce epigenetic instability, specifically interfering with DNA methylation reprogramming events during germ cell and preimplantation development. To date, human studies exploring the association between ART and DNA methylation defects report inconsistent or inconclusive results, likely due to population heterogeneity and the use of technologies with limited coverage of the epigenome. In our study, we explore the epigenetic risk of ART by comprehensively profiling the DNA methylome of 73 human cord blood samples from singleton pregnancies (n=36 control group, n=37 ART/infertility group) from a human prospective longitudinal birth cohort, the Design, Develop, Discover (3D) Study using a high resolution sequencing based custom capture panel that interrogates over 2.4 million autosomal CpGs in the genome.
Results: the main findings We identified striking sex-specific effects of ART on cord blood DNA methylation patterning both genome-wide and for imprinted genes. When compared to less invasive procedures such as in utero insemination, more invasive ARTs (IVF, ICSI, embryo culture) resulted in more marked and distinct effects on the cord blood DNA methylome, including targeting of loci involved in development.
Background: Children conceived through assisted reproduction are at an increased risk for growth and genomic imprinting disorders, often linked to DNA methylation defects. It has been suggested that assisted reproductive technologies (ART) and the underlying parental infertility can induce epigenetic instability, specifically interfering with DNA methylation reprogramming events during germ cell and preimplantation development. To date, human studies exploring the association between ART and DNA methylation defects report inconsistent or inconclusive results, likely due to population heterogeneity and the use of technologies with limited coverage of the epigenome. In our study, we explore the epigenetic risk of ART by comprehensively profiling the DNA methylome of 73 human cord blood samples from singleton pregnancies (n=36 control group, n=37 ART/infertility group) from a human prospective longitudinal birth cohort, the Design, Develop, Discover (3D) Study, using a high resolution sequencing based custom capture panel that interrogates over 2.4 million autosomal CpGs in the genome.
Results: We identified striking sex-specific effects of ART on cord blood DNA methylation patterning both genome-wide and for imprinted genes. When compared to less invasive procedures such as in utero insemination, more invasive ARTs (in vitro fertilization (IVF), intracytoplasmic sperm injection (ICSI), embryo culture) resulted in more marked and distinct effects on the cord blood DNA methylome, including targeting of loci involved in development.
Conclusions: Our study highlights the ability of a sensitive, targeted, sequencing based approach to uncover DNA methylation perturbations in cord blood associated with infertility and ART and influenced by offspring sex and ART technique invasiveness.
