Analysis of Y Chromosome Microdeletions in Individuals with Disorders of Gonadal Development and a 46,XY or 45,X/46,XY Karyotype

Program: Abstracts - Orals, Featured Poster Presentations, and Posters
Session: MON 586-595-Reproductive Axis Determination, Development & Transgender Medicine
Basic/Clinical
Monday, June 17, 2013: 1:45 PM-3:45 PM
Expo Halls ABC (Moscone Center)

Poster Board MON-588
Andrea Maciel-Guerra*1, Ana Paula Santos1, Juliana Andrade1, Juliana De Paulo1, Cristiane Piveta1, Gil Guerra-Junior2 and Maricilda De Mello1
1State University of Campinas, Campinas-SP, Brazil, 2Universidade Estadual de Campina, Campinas - SP, Brazil
Partial and mixed gonadal dysgenesis (PGD and MGD) are characterized by genital ambiguity and the finding of either a streak gonad and a dysgenetic testis or two dysgenetic testes. In PGD there is a 46,XY karyotype, whereas in MGD there is a 45,X/46,XY mosaic or its variants (more than two lineages and/or structural abnormalities of the Y chromosome). These mosaics are also compatible with a female phenotype and Turner syndrome, ovotesticular disorder of sex development, and infertility in men with normal external genitalia. Regardless of the gonadal and genital phenotypes, these individuals present other clinical features associated with the 45,X cell line, including short stature, dysmorphisms, cardiovascular and renal anomalies and various acquired diseases. During the last few years, evidences of a link between Y microdeletions and 45,X mosaicism have been reported. There are also indications that the instability caused by such deletions might be more significant in germ cells. The aim of this work was to investigate the presence of Y chromosome microdeletions in individuals with PGD and in those with 45,X/46,XY mosaicism or its variants and variable phenotypes. Our sample comprised 15 individuals with PGD and 15 with mosaicism, most of them with a MGD phenotype (n=11). Thirty-eight sequence tagged sites (STS) spanning the male specific region (MSY) on the Y chromosome (Yp, centromere and Yq) where analyzed by multiplex PCR and some individual reactions. All STS showed positive amplifications in the PGD group. Conversely, in the group with mosaicism, six individuals with MGD had been identified with Yq microdeletions, two of them did not have structural abnormalities of the Y chromosome recognized by routine cytogenetic analysis. The deleted STSs were located within AZFb and AZFc (Azoospermia Factor) regions, which harbor several genes responsible for spermatogenesis. Absence of deletions in individuals with PGD does not confirm the hypothesis that instability of the Y chromosome in the gonads could be one of the causes of such condition. However, deletions identified in the second group indicate that mosaicism may be associated with Y chromosome abnormalities detectable only at the molecular level. If patients with mosaicism and Y microdeletions reared as males decide to undergo in vitro fertilization, Y chromosomes which tend to be unstable during cell division may be transmitted to offspring.

Nothing to Disclose: AM, APS, JA, JD, CP, GG, MD

*Please take note of The Endocrine Society's News Embargo Policy at http://www.endo-society.org/endo2013/media.cfm

Sources of Research Support: This work was supported by Fapesp (2011/50189-7) and CAPES