Read the Beforeitsnews.com story here. Advertise at Before It's News here.
Profile image
By Alton Parrish (Reporter)
Contributor profile | More stories
Story Views
Now:
Last Hour:
Last 24 Hours:
Total:

Boy or Girl? It’s in the Father's Genes

% of readers think this story is Fact. Add your two cents.


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, published online today by the journal Evolutionary Biology, involved a study of 927 family trees containing information on 556,387 people from North America and Europe going back to 1600.

“The family tree study showed that whether you’re likely to have a boy or a girl is inherited. 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. However, in women, you just can’t predict it,” Mr Gellatly explains.

Men determine the sex of a baby depending on whether their sperm is carrying an X or Y chromosome. An X chromosome combines with the mother’s X chromosome to make a baby girl (XX) and a Y chromosome will combine with the mother’s to make a boy (XY).

The study suggests that an as-yet undiscovered gene controls whether a man’s sperm contains more X or more Y chromosomes, which affects the sex of his children. On a larger scale, the number of men with more X sperm compared to the number of men with more Y sperm affects the sex ratio of children born each year.

Sons or daughters?

A gene consists of two parts, known as alleles, one inherited from each parent. In his paper, Mr Gellatly demonstrates that it is likely men carry two different types of allele, which results in three possible combinations in a gene that controls the ratio of X and Y sperm;

• Men with the first combination, known as mm, produce more Y sperm and have more sons.

• The second, known as mf, produce a roughly equal number of X and Y sperm and have an approximately equal number of sons and daughters.

• The third, known as ff produce more X sperm and have more daughters.

“The gene that is passed on from both parents, which causes some men to have more sons and some to have more daughters, may explain why we see the number of men and women roughly balanced in a population. If there are too many males in the population, for example, females will more easily find a mate, so men who have more daughters will pass on more of their genes, causing more females to be born in later generations,” says Mr Gellatly.

More boys born after the wars

In many of the countries that fought in the World Wars, there was a sudden increase in the number of boys born afterwards. The year after World War I ended, an extra two boys were born for every 100 girls in the UK, compared to the year before the war started. The gene, which Mr Gellatly has described in his research, could explain why this happened.

As the odds were in favour of men with more sons seeing a son return from the war, those sons were more likely to father boys themselves because they inherited that tendency from their fathers. In contrast, men with more daughters may have lost their only sons in the war and those sons would have been more likely to father girls. This would explain why the men that survived the war were more likely to have male children, which resulted in the boy-baby boom.

In most countries, for as long as records have been kept, more boys than girls have been born. In the UK and US, for example, there are currently about 105 males born for every 100 females.

It is well-documented that more males die in childhood and before they are old enough to have children. So in the same way that the gene may cause more boys to be born after wars, it may also cause more boys to be born each year.

How does the gene work?

The trees, below, illustrate how the gene works. It is a simplified example, in which men either have only sons, only daughters, or equal numbers of each, though in reality it is less clear cut. It shows that although the gene has no effect in females, they also carry the gene and pass it to their children.

In the first family tree (A) the grandfather is mm, so all his children are male. He only passes on the m allele, so his children are more likely to have the mm combination of alleles themselves. As a result, those sons may also have only sons (as shown). The grandsons have the mf combination of alleles, because they inherited an m from their father and an f from their mother. As a result, they have an equal number of sons and daughters (the great grandchildren).

Credit: Newcastle University
In the second tree (B) the grandfather is ff, so all his children are female, they have the ff combination of alleles because their father and mother were both ff. One of the female children has her own children with a male who has the mm combination of alleles. That male determines the sex of the children, so the grandchildren are all male. The grandsons have the mf combination of alleles, because they inherited an m from their father and f from their mother. As a result, they have an equal number of sons and daughters (the great-grandchildren).

Contacts and sources:
Newcastle University

Citation: Trends in Population Sex Ratios May be Explained by Changes in the Frequencies of Polymorphic Alleles of a Sex Ratio Gene. Gene Gellatly et al. . Evolutionary Biology, Dec 11, 2008; DOI: 10.1007/s11692-008-9046-3
 



Source:
Before It’s News® is a community of individuals who report on what’s going on around them, from all around the world.

Anyone can join.
Anyone can contribute.
Anyone can become informed about their world.

"United We Stand" Click Here To Create Your Personal Citizen Journalist Account Today, Be Sure To Invite Your Friends.

Please Help Support BeforeitsNews by trying our Natural Health Products below!

Join our affiliate program and earn extra money by sharing with friends and family or by posting on your social media.

Order by Phone at 888-809-8385 or online at www.mitocopper.com


Get our Free Ebook, "Suppressed Health Secrets"  with  Natural Cures THEY don't want you to know!

APeX - Far superior to colloidal silver! Destroys Viruses, Bacteria, Pathogens with Oxygen plus Silver!

Supreme Fulvic - Nature's most important supplement! Vivid Dreams again!

Ultimate Curcumin - Natural pain relief, reduce inflammation and so much more.

MitoCopper - Bioavailable Copper destroys pathogens and gives you more energy. (See Blood Video)
Oxy Powder - Natural Colon Cleanser!  Cleans out toxic buildup with oxygen! 
Organic Hemp Extract (CBD) - Full Spectrum high CBD (3300mg) hemp extract eases stiff joints, relieves stress and more!
Nascent Iodine - Promotes detoxification, mental focus and thyroid health.
Smart Meter Cover -  Reduces Smart Meter radiation by 96%!  (See Video)


FINAL WARNING!  Diseases are EXPLODING!  Watch this Video about APeX and You'll THROW AWAY Your Colloidal Silver!  APeX destroys Viruses, Bacteria and other Pathogens with the power of Oxygen PLUS Silver!  Nobody else has a product like THIS!   See why the inventor hasn't been sick in 16 years and why you'll never hear about it on the FAKE NEWS!  Get some now and tell your friends about it too so we can reach more people!  


APeX Interview - Superior to Colloidal Silver from Lee Canady on Vimeo.


Learn about APeX Here and Get the 50 Page Report in PDF format.   Call us at 888-809-8385 to order by phone.



Report abuse
Loading...
    Loading...

    Comments

    Your Comments
    Question   Razz  Sad   Evil  Exclaim  Smile  Redface  Biggrin  Surprised  Eek   Confused   Cool  LOL   Mad   Twisted  Rolleyes   Wink  Idea  Arrow  Neutral  Cry   Mr. Green

    Total 6 comments
    • The Watcher

      IN DEEP, IT’LL BE A BOY!

      • Rockledge

        Is this your way of telling us you have all daughters?

    • Rockledge

      God determines the gender.

      • PeacePlanet

        ..then the genes answer the call.

        • Rockledge

          Indeed. According to Gods will, not the ramblings of “science”.
          Science being the weak and ill-competent attempts by men to describe Gods many creations in insufficient human language.

    • Mr. Grey

      Boy or Girl? Yeah, can be hard to tell these days.

    MOST RECENT
    Loading...
    Load more ...

    SignUp

    Login

    Newsletter

    Email this story
    Email this story

    If you really want to ban this commenter, please write down the reason:

    If you really want to disable all recommended stories, click on OK button. After that, you will be redirect to your options page.