orientation has been under a glaring spotlight during recent years, with every
right so, due to being neglected and mislabelled for the longest time. Trying
to rectify this mistake, it has produced an abundance of information in a short
time, often invoking similar, but not identical meanings under the same name.
The first step to better understand the differences in sexual development is
accurate labelling and clear nomenclature.
In scientific language
deter any and all misconceptions, terms used in this article are to be looked
at only in context with the text itself. Some of them might have a slightly
different meaning outside of this article or could have a different name
defining a person’s biological function describes the biological role given to
us at the time a foetus is conceived. It is defined by our sexual chromosomes –
XX for a female and XY for male, present throughout the whole body and
persistent through life. It is the biological role which defines if a person
will be born male or female, with a small number of exceptions, and
(un)fortunately, it is permanent. To clarify, a surgical or chemical sex change
will change the appearance of a person together with some of their traits, but
on a biological level, their cells will still have the same chromosomal imprint
they had before the surgical or chemical procedure. To address sexes, male and
female will be used in this article.
Gender is a
cultural and a sociological construct assigned to each sex encouraged by the
sexual evolution of humanity and strengths and weaknesses of sexes, and greatly
varies in different cultures. It is the behaviour associated with a sex, and
the behaviour taught, both actively and passively to a person on the premise of
their sex and the cultural and sociological aspect they find themselves in.
Both gender and its roles can be changed due to a person’s efforts, or as
culture and society evolve. To address genders, men and women will be used in
orientation is the person’s appeal to the members of a particular sex (and
gender). If a person is attracted to a member of the same sex their sexual
orientation is homosexual or gay, and if it is attracted to the opposite sex,
their orientation is heterosexual or straight. If the person is attracted to
both sexes, they are bisexual, and if they are attracted to neither, they are
or cis, and transgender or trans are indicators of sex-to-gender translations.
A female woman is considered a cis-female (or cisgender), and a male woman is
considered a trans-female (or transgender). The same goes for men.
of sexual orientation
of human foetus in sexual terms
understand causes and effects of biological aspects on human sexual
development, we need to visualize the timetable of events that lead to the
onset of a particular sex. First, a sperm cell and an egg cell merge, each carrying
half of their respective parents’ chromosomes. This is the moment at which sex
is determined. Depending on which half of the chromosomes the newly formed
embryo gets, its sexual chromosomes will either be XX or XY – meaning female or
male, respectively. The egg cell, coming from a female, will always give the X
chromosome, so it is up to the sperm cell to determine the sex of the embryo,
as it can either deliver the X chromosome, making the embryo a female, or the Y
chromosome, making it male.
There is a
difference in size, as well as in function between X and Y chromosome. How
specifically they give rise to either a female or a male sex is still not fully
understood, but, because they contain different DNA, it is easy to see that
some differences have to exist.
accordance with their respective chromosomal pair, female or male gonads
(sexual organs) are developed. They develop based on presence or absence of
androgen hormones, mainly testosterone, dihydrotestosterone and androsterone,
which are present or absent based on the chromosomal pair available. Production
of testosterone and conversion into dihydrotestosterone in weeks 6 to 12 of
pregnancy are key factors in the production of a male foetus’s genitals.
Absence of those hormones leads to development of female genitals.
genitals are formed, they release their own set of hormones, together with
other chemical factors that shape further development of the foetus. Sexual
differentiation of the brain occurs, among other factors, under the watch of
sex hormones derived from gonads, with which they exert organizational effects
that will activate in puberty.
of genital femininity or masculinity doesn’t necessary relate to their
counterpart in the brain, as those processes occur separately. Organizational
differences between sexes have been found throughout the brain, most notably in
the hypothalamus and amygdala. Differences in brain structure present due to
chemical influences (hormones and other chemical messengers) are believed to be
the basis of different sexual orientation and gender preferences.
mind both the influence of chemical messengers and the different time points at
which gonads and brain sexually develop, it is easy to understand that exposure
to different hormones and different concentrations of hormones can affect
sexual orientation and gender preferences in adults.
almost everything else in biology, foetal hormones are not the only influencers
in sexual orientation, but are probably the main ones. Together with genes and
environmental conditions, as well as external chemical factors, they influence
One of the
evidences for such claim comes in form of a condition called Congenital Adrenal
Hyperplasia, or CAH. It is a genetic disorder that results in exposure to high
levels of androgen hormones in early pregnancy due to hyperactivation of adrenal
glands. Females with CAH are born with masculinized genitalia, and are more
likely to be homosexual, in comparison to the overall population.
other factors, observed in higher percentages in homosexual population, can
influence sexual orientation. Some aspects of prenatal stress levels, as well
as several drugs can change the outcome of sexual orientation and/or gender
preference. Severe psychical traumas, such as war, severe mental shock and
death of a loved ones have been linked to having an impact on sexual
orientation. Psychostimulants abuse has been debated as well as to having an
impact, but both cases need further research.
birth order effect
It has been
established that gay males have on average more older brothers. This is due to
the increasingly higher level of androgen hormones foetuses are exposed to with
every male pregnancy. Additionally, this phenomenon is explained by the
immunological response of the mother to a product of Y chromosome of her sons,
which also increases with every male pregnancy. A gene of the Rhesus factor
(Rh), a protein found on the red blood cells, has been linked to this effect.
Rh factor can be inherited from either parent, with a slight chance of a
mother’s immune response to a father’s Rh factor in the foetus. Each
consecutive male pregnancy slightly increases the mother’s immune response to
the Rh factor, with cumulative effect.
background also shapes sexual orientation. Additionally, several studies found
chromosomal differences between homosexual and heterosexual people, especially
on chromosome 11, tied to olfactory functions and visual perception. Prior
studies have determined those regions to be linked with perception of pleasure
in both males and females.
these factors are either a cause or an effect of an immunological, endocrine or
genetic mechanism observed over the years as small, albeit statistically
scales of sexual orientation
One of the
obstacles in research of sexuality was misconception and mislabelling of
research materials, as well as sexual groups. For the longest time sexual
orientation was considered as an either-or scenario, with odd cases of both or
neither in between. In recent times, sexual orientation has been classified as
a sliding scale, greatly easing both research and nomenclature.
can identify as straight, have only partners of the opposite sex, and still
express some form of sexual attraction, be it periodical or continual, to the
members of the same sex. That person might still consider themselves as purely
heterosexual and never have a homosexual relation, whether by choice or by not
having the opportunity to express these tendencies, or simply because the
attraction isn’t strong enough. It can be seen as a percentage of being
heterosexual or homosexual.
sliding scale can be used to determine gender, as it is a sociocultural
construct, rather than a biological one. It is that same sociological and
cultural environment that needs to be taken into account when considering the
re-emergence of both problems around sexual orientation and gender identity.
of culture and society
and sociological determination of an idea is the individual’s choice to accept
a higher power’s interpretation of that idea. For a long time that power was
religion, with its hold still strongly affecting the individuals’ comfort level
and awareness regarding sexual orientation. Such powers, both directly -
through teachings, laws or other means, or indirectly - through social
appreciation, human interaction and example, have pushed the sexuality towards
one end of the sliding scale while marginalizing the rest. As expected, apart
from social ignorance, this can lead to several medical conditions.
orientation is in part also taught, with the most influential teachers being
the ones closest to us.
religion, country laws are the second biggest power that actively forms social
and cultural ideas. In recent times, European union has a rising, albeit slow
tendency towards actively enforcing laws for the betterment of gay populations.
While there is no more laws directly against being gay, the nonexistence of
laws for their benefit also influences their choices, to a degree. A bisexual
person might opt for a heterosexual relationship because of marriage
privileges, or similar benefits such a relationship can bring, in contrast to a
for the same sex, if not very prominent, can be stifled by the environment. The
person might never know they have a tendency towards the same sex, or they
could find it out much later in life. This is especially true for developing
children, who are most susceptible to learn by examples. Subtle signs of
heterosexual relations are all around us, from wedding rings, couples holding
hands and children amidst parents. Homosexual relations are still a much rarer
to every rule
delicate the sex-to-gender transition can be, and how many factors actively and
passively take part in shaping a person’s sexuality, it is no wonder that
sometimes things go awry.
inbetweeners: chromosomal aberrations
of sex chromosomes are rare conditions where an individual doesn’t have the
usual XX or XY chromosomes. One problem that can happen is the deletion of a
part of such a chromosome. Effects of such deletions are proportional to their
severity, but also correspond to the part of the chromosome that has been
but more severe type of this condition is so called Turner syndrome, also known
as 45,X or 45,X0 syndrome. It is a genetic condition in which a female is
missing a part or a whole X chromosome. They are characterized by a short and
webbed neck, low-set ears and short statue. Typically, they are unable to
the Turner syndrome is the Triple X syndrome, also known as trisomy x. It is
characterized with an extra X chromosome in female’s cells that ensues when a
sperm cell fertilizes an egg cell that has two X chromosomes instead of one.
Such females are usually taller than average, with occasional mental and
syndrome is a similar occurrence, where a sperm cell containing Y chromosome
fertilizes an egg cell containing two X chromosomes, or a sperm cell containing
X and Y chromosome fertilizes a normal egg cell. The primary features are
infertility and small poorly functional testicles, often not even noticed.
dysgenesis is a rare condition where no functional ovaries are present to
induce puberty in an otherwise normal female.
Such persons usually have a demonstrable abnormality in one of the sex
chromosomes. It is inherited as an autosomal disease, and is, to an extent,
treated with hormonal therapy.
dysgenesis, also known as Swyer syndrome, is a similar condition in a person
who has the male sex chromosomes, but due to their aberrations hasn’t developed
male genitalia, and in term, due to reasons discussed above, has developed
female external genitalia and secondary female features.
is a term meaning “a state of unease or generalized dissatisfaction”, and comes
with a stigma attached to it. It has been renamed from gender identity disorder
in 2013. Both gender and sexual orientation dysphoria appear when a person is
expected (or forced) to behave as one side of the sliding scale, while they
feel as belonging to another.
gender noncomformity is a state similar to dysphoria, but without “clinically
gender dysphoria have been linked to prenatal androgen exposure and
discrepancies between genital and cerebral femininity or masculinity, as
discussed above. Gender dysphoria can also occur when a male is brought up as a
woman, or a female as a man, in otherwise healthy individuals. Etymology of
such dysphorias remain mostly unknown, as they can (and usually are) the
interplay between biological, chemical, environmental and culturological
for gender dysphoria include incongruence between a person’s experienced or
expressed gender and their primary sex characteristics, a desire to be rid of
existing primary or secondary sex characteristics or the desire for those
characteristics of the opposite sex.
International Classification of Diseases (IDC-11) aims to rename gender
dysphoria to gender incongruence, which would be described as “a marked and
persistent incongruence between an individual’s experienced gender and the
body of research has been done in recent years that has improved the way we
think about sex, gender and sexual orientation. With it, improved nomenclature
and unambiguous terms have emerged easing further research. That being said,
any term used to either entitle or marginalize a person above or below another
person should be shunned and frowned upon. It is not the words and titles that
are good or bad, it is the person behind them and their intentions. And all we
need for a thriving community are good intentions, understanding and some love.
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