Only God knows how many of you this would interest...
but while i was going through one of the biology journals i came across, the stories and illustrations were interesting and evident.
Okay, this isn't a blue scene, it is actually true...
some people are already getting excited already, when they heard that this was going to be published...
According to the biology textbooks and journal, Males with an extra girly sex chromosome two (X chromosomes) seemed to have an insatiable appetite for sex, at least in mice.
for biological sciences, @least the ones in Redeemers University, we are all conversant with the fact that In mammals, gender is determined by sex chromosomes, the X and Y. If you
have two X chromosomes, you are a female. If you have one X and one Y,
you are a male. (Chromosomes are long strings of DNA that hold many
genes; humans have 23 pairs of chromosomes, one set inherited from each
parent.)
The study was done in mice, not humans sha, but the genes that determine sex are similar in mammals, so the results might be applicable definately, especially in males with Klinefelter’s syndrome(a condition in which human males have an extra X chromosome, While females have an XX chromosomal makeup, and males an X ), who are genetically XXY.
“Whether this is a specific phenomenon to mice, or even to this
particular inbred background strain of laboratory mice, is still an open
question, but we did find similar results in two different genetic
models of mice,” study researcher Paul Bonthuis, a graduate student at
the University of Virginia, told LiveScience in an email.
“To know how general the finding is to other mammals one would have
to do studies with other mammalian species directly,” he noted.
The researchers studied two special lines of mice.
In the first, they were able to separate the effects of the X and Y
chromosomes from the mouse’s sexual development (which is dependent on
one gene on the Y chromosome). This means that even lab mice with odd
numbers of sex chromosomes - for instance males with two X’s or females
that have a Y - still developed normally; they had normal genitalia and
sexual behaviours for their gender.
In another genetically engineered mouse model the researchers linked
the X and Y chromosome so this pair could be matched up with an X
chromosome, resulting in genetically XXY males.
These two models provided different parts of the puzzle, with the
first one revealing developmental differences created by genes on either
the X or Y chromosome that aren’t involved in normal development. The
second model would reveal how an extra X chromosome affected the male
mice.
Sex hormone levels were normal in all of these special lines of mice.
When they studied these mice, they found that the males with two X
chromosomes (the XXY males) were about twice as fast to ejaculate and
ejaculated nearly twice as often than those with only one. They also
mounted females more often and during sex showed more pelvic-thrusting
motions.
“We take these findings to mean that not all sex differences in
behaviour are due to the differences in the hormone secretions by the
ovaries and the testes,” Bonthuis said.
“Our studies indicate that direct genetic differences between XX and
XY individuals ... also play a role in causing sex differences in
behaviour,” he stated.
These results indicate that there may be an undiscovered gene on the X
chromosome that affects sexual behaviours in mice and perhaps in other
mammals, the researchers say.
“We do not yet know what gene on the X chromosome is causing this
effect on behaviour,” Bonthuis said, but only a small percent of genes
are expressed on both X chromosomes (some genes are automatically turned
off in one X when two X chromosomes are present).
“It is hard to say for certain what the X factor could be, but we do have some likely candidates,” he asserted.
Human males with two X chromosomes do exist. They have Klinefelter’s
syndrome, which happens about once every 500 to 1,000 male births.
Symptoms include infertility and decreased testosterone levels, among
others. Many males don’t show symptoms.
A 1997 report on men with lowered fertility indicated that men with
Klinefelter''''s reported having sexual intercourse more than
normal XY males. If this holds true, they could be under the influence
of the same mysterious X chromosome factor as the mice.
The study was published online and also on my biology textbook too, last month in Hormones and Behavior.
