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Friday, June 27, 2014

hermaphroditism

Alberto says:  Just recently, I watched over ch 2 TFC channel a guy who was interviewed disclosing that he has two genital organs: that of a male and female. He was claimed to be a hermaphrodite.
A hermaphrodite describes a person who is born with both female and male physical characteristics.

Increasingly, however, intersex is becoming a more popular description when referring to individuals of this congenital state.

A hermaphrodite may be born with both sex organs or may be born with one main sex organ, but possess part of a second opposite organ.

Beyond visible features, other physical characteristics may also cause a person to be defined as intersex, such as the chromosomal differences apparent in Klinefelter syndrome where a male is born with two X chromosomes and one Y chromosome.

Aside from having an ambiguous-looking external genitalia, true hermaphroditism in humans differs from pseudohermaphroditism in that the person's karyotype has both XX and XY chromosome pairs (47XXY, 46XX/46XY, 46XX/47XXY or 45X/XY mosaic) and having both testicular and ovarian tissue.

One possible pathophysiologic explanation of this rare phenomenon is a parthenogenetic division of a haploid ovum into two haploid ova.

Upon fertilization of the two ova by two sperm cells (one carrying an X and the other carrying a Ychromosome), the two fertilized ova are then fused together resulting in a person having dual genitalial, gonadal (ovotestes) and genetic sex.

Another common cause of hermaphroditism is the crossing over of the SRY from the Y chromosome to the X chromosome during meiosis.

 The SRY is then activated in only certain areas, causing development of testes in some areas by beginning a series of events starting with the upregulation of SOX9, and in other areas not being active (causing the growth of ovarian tissues).

Thus, testicular and ovarian tissues will both be present in the same individual.

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