© Freund Publishing House Ltd., London Journal of Pediatric Endocrinology & Metabolism, 22, 1083-1086 (2009) Mixed Gonadal Dysgenesis in a 45,X Neonate with Chromosome Õ Material in the Dysgenetic Gonad Ageliki Karatza 1 , Dionisios Chrysis 1 , Eunice-Georgia Stefanou 1 , Stefanos Mantagos 1 and Christos Salakos 2 'Department of Pediatrics and 2 Department of Pediatric Surgery, University ofPatras Medical School, Greece ABSTRACT We report on a neonate with a disorder of sex development, Prader 3-4 external genitalia and a palpable structure in the right inguinal canal suggestive of gonadal tissue. Chromosome studies on blood lymphocytes showed monosomy of chromosome X. Laparoscopy identified a streak- like gonad on the left side, unicorn uterus and a dysgenetic testis on the right, attached to a Fallopian tube. Because of the unilateral pal- pable gonad and the presence of ambiguous genitalia we investigated further for the presence of Õ material. Quantitative fluorescent PCR analysis of material from the dysgenetic gonad and skin fibroblasts revealed the presence of chromosome Y-derived sequences, suggesting sex chromosome mosaicism. In 45,X/46,XY mosaicism, chromosome studies carried out on peripheral lymphocytes do not always reflect the proportion of cell lines in the gonads. The detection of Õ chromosome material in a dys- genetic gonad is extremely significant, due to the high risk of malignant transformation. INTRODUCTION Mixed gonadal dysgenesis (MOD), a disorder of sexual differentiation, is characterized by the asymmetrical presence of dysgenetic testicular tissue. There is a considerable variability of pheno- type which can range from normal male to normal female, through the whole spectrum of ambiguity. The etiology is variable and sex chromosome mosaicism, in which 45,X karyotype is combined with a cell line that contains a normal or abnormal Õ chromosome, represents one of the important causes 1 . On the other hand, not all patients with 45,X/ 46,XY mosaicism have MGD. A wide phenotypic spectrum has been reported in children with 45,X/ 46,XY mosaicism. Females usually have Turner's stigmata. Turner's syndrome is characterized by the presence of certain physical features in phenotypic females with complete or partial absence of one of the sex chromosomes, with or without cell line mosaicism. Phenotypic males or ambiguous cases, independently of the karyotype, are not considered as Turner's syndrome. KEY WORDS mixed gonadal dysgenesis, 45,X/46,XY mosaic, QF-PCR analysis, Turner's syndrome, disorder of sex development Reprint address: Christos Salakos, M.D. Department of Pediatric Surgery General University Hospital ofPatras 26504, Rio, Patras, Greece e-mail: csalakos@otenet.gr PATIENT REPORT An intersex neonate was born at 41 weeks of gestation, of a healthy 24 year-old primigravida with normal vaginal delivery. Rupture of mem- branes occurred 3 hours prior to delivery, amniotic fluid was mildly meconium stained, birth weight was 3,445 g and Apgar score was 7 at the 1 st and 10 at the 5 th minute of life. Both antenatal and family history were unremarkable. The mother denied use of any medication during pregnancy and the parents were non-consanguineous. Cardiac and renal ultra- sounds were normal. VOLUME 22, NO. 11,2009 1083 Brought to you by | University of California - San Francisco Authenticated Download Date | 2/19/15 5:50 PM