Autism, imprinting and epigenetic disorders: a metabolic syndrome linked to anomalies in homocysteine recycling starting in early life??

Excerpt

An association between imprinting syndromes and ART is now common knowledge. Imprinting problems are roughly linked to DNA methylation disorders, and clinical reports of ART-linked imprinting syndromes have implicated hypomethylation of the maternal alleles (1). Kattari et al. (2), examining DNA methylation in 700 genes, observed different levels of methylation between children conceived in vitro and in vivo. They also found that the differences observed in DNA methylation in the children conceived in vitro involved differences in gene expression for both imprinted and non-imprinted genes. This effect is observed even when maternal age is taken into account. We recently pointed out some aspects of in vitro and in vivo parameters that could be responsible for impairment of methylation processes in ART patients (3), in particular an increased concentration of homocysteine (Hcy) in the oocyte environment. …