"Although the role of the X and Y chromosomes is to produce two discrete populations of male and female humans, the way they are inherited means that babies can be born which are 'intersex': neither fully male nor female." --Making Babies page 153The LDS church claims that "Gender is an essential characteristic of individual premortal, mortal, and eternal identity and purpose." Apparently the men responsible for creating this doctrine weren't biologists--nor did they bother to look into science to see if the above statement is true.
George Williams, in his book The Pony Fish's Glow : And Other Clues to Plan and Purpose in Nature, discusses the biological occurrence in which a person is born with two sets of DNA. How does this happen? Two eggs in the womb can be fertilized. This occurs naturally, although infrequently, in nature. Sometimes neither fertilized egg survives, sometimes both do (and result in non-identical twins), and sometimes they fuse together during the pregnancy creating one person (by the time birth occurs) from two separate fetuses. The person can have two sets of male or female DNA, or they can have both male and female DNA simultaneously. This latter instance is sometimes discovered when the person exhibits both male and female genitalia. Otherwise, the person can go undetected as both male and female unless other medical difficulties arise within the person due to the two sets of DNA.
On January 14, 1998 the following news was released by Reuters:
Medical researchers in Britain have found an unexpected risk in the implantation of more than one fertilized egg in the womb of a woman undergoing in vitro fertilization. They have found a case in which two embryos, one male and one female, fused in development to form a single child.What does all this mean? For starters, people and religions that are sexist (and 'genderist' in the case of Mormonism) should take a step back and rethink their ideas, policies, and doctrines. Perhaps those in power in the all-male Mormon hierarchy should have DNA tests done on their various body tissues to make sure that they are as male as they claim to be.
The case, outlined in Thursday's New England Journal of Medicine, surfaced when an otherwise healthy child was treated because his left testicle had not descended normally. Surgeons discovered an ovary and a fallopian tube on the left side. Otherwise the child, now in school, has developed normally.
In medical terms, the child is known as a chimera, named after the mythical Greek monster that was part lion, part goat and part serpent.
The researchers, led by Lisa Strain of the University of Edinburgh, said the standard practice of implanting more than one embryo during in vitro fertilization made it possible for the two embryos to fuse.
"The observation of chimerism after in vitro fertilization should therefore be taken seriously," they said. Such phenomena can happen naturally, but it is very rare, so rare as to "suggest a causal link to the in vitro fertilization," they said.
There may be more cases of chimerism than people realize, the Strain team speculated, because fusions between two male embryos or two female embryos would probably be missed since the baby would show no sex organ abnormalities.
The risk of chimerism has risen in recent years because more women are taking fertility drugs, which release multiple eggs for fertilization. Couples are also using in vitro fertilization, in which doctors routinely implant more than one fertilized egg to increase the likelihood that at least one will develop into a viable fetus.
The higher rate of multiple births after the use of fertility drugs or in vitro fertilization also means that more chimeric children may be found. In the United States and Canada, fertility drugs and in vitro fertilization techniques produce twins 28 percent of the time and triplets 6 percent of the time. The normal rates are 1 percent and 0.013 percent.
A fairly new book has been written on a related subject entitled Hermaphrodites and the Medical Invention of Sex. I suppose it could also have been named Hermaphrodites and the Mormon Invention of Eternal Gender if Mormon doctrine was included in the study. ;)
Also see Chapter 11 in Lucy's Legacy entitled "A Gendered Body" and the section entitled "The Determinants of Sex" beginning on page 353 of Science As a Way of Knowing: The Foundations of Modern Biology. Finally, you will not want to miss pages 153 through 157 (and pages 36 and 37 for the story of F.D., a male/parthenogenote chimaera) in Making Babies: The Science of Pregnancy which deals with guevedoces and other "non-eternal" gender issues.