Polycystic ovarian syndrome (PCOS) is an endocrine and metabolic
dysfunction, highly prevalent in women in their reproductive years.
Hyperandrogenism, oligo-ovulation, polycystic ovarian morphology are
the main features of this syndrome. PCOS is a genetic disorder with a
multifactorial etiology and has a strong link with environmental components.
It is frequently associated with obesity and insulin resistance.
Recently, epigenetic mechanisms have been involved in the pathogenesis
of PCOS. Several studies showed that methylation in DNA and miRNAs
is altered in women with PCOS in blood, serum, adipose tissue, granulose
cells and theca. This evidence indicates that women with PCOS have a
different epigenetic regulation, which might be triggered by an adverse
intrauterine environment or by postnatal environmental elements such
as diet and or obesity.