A dispermic chimerism in a 2-year-old Caucasian boy

• Published in: Annals of hematology Vol. 78; no. 9; pp. 431 - 434
• Main Authors: REPAS-HUMPE, L. M, HUMPE, A, LYNEN, R, GLOCK, B, DAUBER, E. M, SIMSON, G, MAYR, W. R, KÖHLER, M, EBER, S
• Format: Journal Article
• Language: English
• Published: Berlin Springer 01.09.1999; Springer Nature B.V
• Subjects: Biological and medical sciences; Blood Grouping and Crossmatching; Child, Preschool; Chimera; Disorders of Sex Development - genetics; Genitalia, Male - abnormalities; Gynecology. Andrology. Obstetrics; Humans; Male; Male genital diseases; Medical sciences; Non tumoral diseases; Phenotype; Endocrinopathy; Human; Genetic variability; Male; Congenital disease; Genital diseases; Case study; Gene; Malformation; Hermaphroditism; Genetics; Chimerism; Child; Polymorphism
• ISSN: 0939-5555; 1432-0584
• DOI: 10.1007/s002770050543

Detection of two different cell populations in a child is a rare event. The following case of a dispermic chimera was diagnosed before surgery due to problems in blood group determination. A 2-year-old phenotypically male child was admitted for correction of a penoscrotal hypospadia and unilateral cryptorchism. During presurgical laboratory investigation, difficulties in blood group determination occurred. Blood group typing was performed by the DiaMed-ID Micro Typing System and by FACS. Additionally, cytogenetic analysis of lymphocytes and analysis of DNA polymorphisms in different tissues were performed. Two populations of red blood cells were detected, O cells accounting for 75% and B cells for 25%. Analysis of DNA-PCR polymorphisms in lymphocytes, nails, and in cells of the oral mucous membrane demonstrated a chimerism, with two alleles inherited from the father and one from the mother. A cytogenetic analysis of cultured lymphocytes showed a mosaic 46, XY/46,XX. Surgery revealed a prostatic utricle grade III, also called pseudovagina; genitography confirmed a vagina. Bilateral gonad biopsy showed a testis on one side and an ovary on the other. This case of chimerism represents a true hermaphroditism that most probably developed by double fertilization of one or more egg nuclei by two sperms.