title: Developmental instability of ano-genital distance index: Implications for assessment of prenatal masculinization.
abstract: Prenatal androgens are generally assumed to permanently affect the morphology of external genitalia. In laboratory rodents, the ano-genital distance index (AGDI) has become widely used as a marker of natural prenatal masculinization. A greater value should indicate a greater masculinization. The aim of this study was to assess the developmental stability of the AGDI in female mice during pre- (Days 1-21) and postweaning (Days 21-61) periods. Presuming that the AGDI reflects a permanent effect of prenatal masculinization, we hypothesized that the AGDI will be a developmentally stable morphometric measurement (interindividual differences in the AGDI measurement should persist over time). In contrast to our prediction, the AGDI showed poor repeatability both during pre- (.15) and postweaning (.22) periods, indicating developmental instability. (A value of 1 indicates perfect repeatability and a value of 0 indicates no repeatability.) The AGDI thus does not seem to be a reliable marker of prenatal female masculinization.
authors.affiliation: Department of Ethology Institute of Animal Science, Prátelství 815, CZ-10400 Praha, Czech Republic. adamdusek@yahoo.com
authors.forename: Adam
authors.initials: A
authors.lastname: Dusek
authors.forename: Ludek
authors.initials: L
authors.lastname: Bartos
authors.forename: Frantisek
authors.initials: F
authors.lastname: Sedlácek
mesh_terms: D001003:Anal Canal / Q000033:anatomy & histology* / Q000196:embryology*; D000704:Analysis of Variance; D000818:Animals; D001837:Body Weights and Measures; D005260:Female; D005836:Genitalia, Female / Q000033:anatomy & histology* / Q000196:embryology*; D051379:Mice; D010502:Perineum / Q000033:anatomy & histology* / Q000196:embryology*; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D015203:Reproducibility of Results