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Girls guys sperm

Since the late s, scientists have explored how to produce sperm where all of the chromosomes come from a female donor. Creating female sperm was first raised as a possibility in a patent filed in [3] by injecting a woman's cells into a man's testicles, though the patent focused mostly on injecting altered male cells into a man's testes to correct genetic diseases. In , Japanese scientists partially confirmed such techniques by creating chicken female sperm in a similar manner. It is therefore concluded that most of the W-bearing PGC could not differentiate into spermatozoa because of restricted spermatogenesis. One potential roadblock to injecting a woman's cells into a man's testicles is that the man's immune system might attack and destroy the woman's cells.
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8 ways a man is unknowingly damaging his sperm count | Daily Mail Online

A new chemical treatment that can segregate male and female sperm could one day mean parents going through IVF could choose whether they have a boy or girl. In experiments with mice sperm, scientists found they could produce litters that were 90 per cent male, according to the study published in Plos Biology. When the slower sperm were used, litters were 81 per cent female. The X chromosome has many genes while the shorter male Y chromosome has fewer, and this difference in gene expression meant scientists could distinguish between the two.
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Is Sperm Actually Good for Skin? And 10 Other FAQs

By Claudia Tanner For Mailonline. Many couples experience fertility problems and low sperm count can be a key factor. Sperm counts in men worldwide have declined by half over the past 50 years and are continuing to fall, according to recent reports. But before you rush for anxiety-inducing tests, there are plenty of things a man can do to help things along and make sure his swimmers are in good nick.
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A Newcastle University study involving thousands of families is helping prospective parents work out whether they are likely to have sons or daughters. The work by Corry Gellatly, a research scientist at the university, has shown that men inherit a tendency to have more sons or more daughters from their parents. This means that a man with many brothers is more likely to have sons, while a man with many sisters is more likely to have daughters. The research involved a study of family trees containing information on , people from North America and Europe going back to We now know that men are more likely to have sons if they have more brothers but are more likely to have daughters if they have more sisters.
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