Gender Spectrum (Part 1)
As part of a school biology course, everyone learns that sex is predetermined by a set of chromosomes. Indeed, as a rule, in humans, women have the genotype XX, and men have XY. Other species have other mechanisms.
There are a huge number of intermediate stages between a chromosome – a DNA molecule – in a sperm or egg and the formation of sexual organs, the ability to produce germ cells and, finally, the self-perception of an adult. At each of these stages, something can go wrong. Not all deviations from the norm in the course of individual development are fatal. The deviations that allow the body to be born and grow are very different in their impact on the quality of life. Some really make ordinary life impossible, others deprive them of the opportunity to have their own children. The traumatism of the third, for example, the discrepancy between anatomical gender and self-perception depends on the mood in society. With the fourth, you can live your whole life and not guess about them.
In 2010, a 46-year-old woman pregnant for the fourth time turned to Australian doctor Paul James. She already had two healthy daughters. Pregnant women at this age are recommended to perform a genetic examination of the fetus, since the risk of chromosomal diseases (for example, Down syndrome) increases with the age of the mother. The child turned out to be healthy, but the results of the accompanying tests of the mother greatly surprised the doctors. 65% of her blood cells contained genotype XY, and only 35% contained genotype XX. Analysis of other tissues confirmed that the woman turned out to be a chimera.
Chimeras are born when several eggs are fertilized at the same time (in the vast majority of cases two), and the embryos merge. If the embryos had not merged, fraternal (heterozygous) twins would have been born. Basically, it doesn't have any devastating consequences. Such people look and feel like the most ordinary people, so it is still unknown how often chimera people are actually born.
The case of Lydia Fairchild, suspected of illegally using the services of a surrogate mother and trying to deceive the state, is noteworthy. After parting with the father of her three children, she turned to social services for help, the services demanded confirmation of paternity. As a result, it turned out that the alleged father was really the father, but Lydia herself, judging by genetic analyses, was someone else's aunt to her children. The collision was resolved only after Lydia's chimerism was assumed and cells from other tissues were taken for genetic analysis.
In the vast majority of cases, when chimerism is not a random finding, it is detected due to abnormalities of the reproductive system caused by the presence of XX and XY cells. Such people often have both female and male genitals, they have difficulties when trying to have children. The patient of Paul James, despite the late age of marriage, became a mother three times. Most likely, this was due to the fact that XY cells were not among the cells of the embryo from which the genitals developed.
In 2014, a 70-year-old man, the father of 4 children, was operated on for an inguinal hernia in Kashmir. And they found... a uterus. For the last 20 years, the patient has had asymptomatic inguinal lymphadenitis, and has not had one testicle since birth. Otherwise, he was quite healthy, the genotype was normal.
The two cases described have one thing in common: in them, people are absolutely sure what gender they are, they got married and gave birth to healthy children. Their differences from other people were accidental findings and could not affect anything. Much more difficult from an ethical point of view is the situation when a child is born with signs of both sexes. What should doctors do? Surgical intervention in one direction or the other is easiest to carry out when the child has just been born, and then educate in the appropriate way. But do parents or guardians have the right to choose for the child? What happens if they choose the wrong one? A child usually begins to show gender-colored behavior around the age of three. Wouldn't it be better to wait until then? Or until the child becomes an adult and can make a decision on his own? But it will be quite difficult for such a different child to live in society. Isn't it better to minimize differences surgically at a very early age? But does anyone have the right to choose for a person?
Discussions about this began to arise in connection with the case of patient MC. The child was born 8 years ago in South Carolina and was given up for adoption. He (she) was born with signs of both sexes. The biological parents of the child turned out to be, and when he was in the care of the state, the doctors decided to perform surgery, leaving only the female genitals. The child was adopted, and some time later it became clear that he felt like a boy. Since then, lawsuits have begun: not only against the doctors who performed the operation, but also against the state of South Carolina, which was the guardian at the time of the operation. Recently, the plaintiffs were refused to transfer the case to the federal level, but the case continues at the state level.
It is already clear that not all people can be definitely divided into men and women. According to some (rather bold) estimates, about one person out of a hundred is born and grows up with certain disorders in the formation of gender. The rights and interests of these people must be taken into account. Probably, for this we will have to admit that the binary concept of gender is outdated, and it is worth trying to consider gender as a continuous spectrum. Recently, more and more scientific data has begun to appear, forcing us to do so.
To understand where the intermediate states come from, it is worth remembering exactly how the development of sex occurs.
In the first approximation, gender is determined by the genotype of the organism. But even here, as we have seen, options are possible. In addition to chimerism at the level of fusion of two embryos, there is microchimerism – when fetal cells enter the mother's body, the mother's cells enter the fetus's body, and the twins exchange cells with each other. Usually in such cases we are talking about small amounts of cells, but in several studies it has been shown that, for example, fetal cells can persist in the mother's body for a very long time. Cells with the XY genotype were found at autopsy in the brain of a 93-year-old woman who had a son. Moreover, it has been shown that these cells do not sit idle – they integrate into the environment and perform quite specific functions – for example, they become neurons of the brain. There is no answer yet to the question whether the presence of "male" cells in the brain of women affects higher nervous activity. But some studies demonstrate that in vitro experiments, the metabolism of cells with genotypes XX and XY differs.
The end of the article is here.
Portal "Eternal youth" http://vechnayamolodost.ru02.03.2015