True hermaphroditism is a medical term for an intersex condition in which an individual is born with ovarian and testicular tissue.
There may be an ovary underneath one testicle or the other, but more commonly one or both gonads is an ovotestis containing both types of tissue.
There are no documented cases in which both types of gonadal tissue function. Encountered karyotypes are 47XXY, 46XX/46XY, or 46XX/47XXY, and various degrees of mosaicism (with one interesting case of an XY predominant (96%) mosaic giving birth).
Although similar in some ways to mixed gonadal dysgenesis, the conditions can be distinguished histologically.
Although fertility is possible in true hermaphrodites (as of 2008 there have been at least 11 reported cases of fertility in true hermaphrodite humans in scientific literature), there has yet to be a documented case where both gonadal tissues function; contrary to rumors of hermaphrodites being able to impregnate themselves.
External genitalia are often ambiguous, the degree depending mainly on the amount of testosterone produced by the testicular tissue between 8 and 16 weeks of gestation.
This condition is very rare. There are several ways in which this may occur.
- It can be caused by the division of one ovum, followed by fertilization of each haploid ovum and fusion of the two zygotes early in development.
- Alternately, an ovum can be fertilized by two sperm followed by trisomic rescue in one or more daughter cells.
- Two ova fertilized by two sperm will occasionally fuse to form a tetragametic chimera. If one male zygote and one female zygote fuse, a hermaphroditic individual may result.
- It can be associated with mutation in the SRY gene.
- ^ http://www.ncbi.nlm.nih.gov/pubmed/18394621
- ^ a b Kim KR, Kwon Y, Joung JY, Kim KS, Ayala AG, Ro JY (October 2002). "True hermaphroditism and mixed gonadal dysgenesis in young children: a clinicopathologic study of 10 cases". Mod. Pathol. 15 (10): 1013–9. doi:10.1097/01.MP.0000027623.23885.0D. PMID 12379746.
- ^ Braun A, Kammerer S, Cleve H, Löhrs U, Schwarz HP, Kuhnle U (March 1993). "True hermaphroditism in a 46,XY individual, caused by a postzygotic somatic point mutation in the male gonadal sex-determining locus (SRY): molecular genetics and histological findings in a sporadic case". Am. J. Hum. Genet. 52 (3): 578–85. PMC 1682159. PMID 8447323.