Principles of phenomics in endometriosis

Endometriosis has been associated with specific morphometric characteristics and pigmentary traits. The purpose of this study was to systematically review prior publications dealing with this aspect in order to revisit phenotypic information in the context of phenomics principles. Comprehensive searches of Pubmed, Medline and Embase were conducted to identify studies, published from 1990 to 2011 in the English language literature, on the relationship between endometriosis and morphometric characteristics/pigmentary traits. We identified 11 studies on the association between endometriosis and body mass index (BMI) in the adult population and 5 studies on the same association during early life. While a modest inverse correlation was found between endometriosis and adult BMI, a stronger association was consistently demonstrated between endometriosis and early life body size, even after adjusting for confounding factors such as age, birthweight, age at menarche, parity and oral contraceptive use. Four papers have been published on the association between endometriosis and cutaneous naevi and five on the association between the disease and specific pigmentary traits. A skin phenotype characterized by the presence of naevi and freckles and by a high sensitivity to sun exposure is represented more frequently in women with endometriosis. Endometriosis appears to be associated with some phenotypic variations likely attributable to the strong effect of the environment on the expression and function of genes influencing the traits. Novel clues on endometriosis pathogenesis may derive from the analysis of the phenotypic traits associated with the disease.