GENES PLEASE HELP !!!

Genetics as it applies to evolution, molecular biology, and medical aspects.

Moderators: honeev, Leonid, amiradm, BioTeam

Post Reply
j_todorov
Garter
Garter
Posts: 2
Joined: Mon Apr 23, 2007 4:15 pm

GENES PLEASE HELP !!!

Post by j_todorov » Mon Apr 23, 2007 4:22 pm

Can two parents, who have blue eyes ,to have a child with brown eyes?

User avatar
kotoreru
Coral
Coral
Posts: 400
Joined: Thu Apr 12, 2007 9:25 pm
Location: London

Post by kotoreru » Mon Apr 23, 2007 4:48 pm

No. Not unless there is a mutation or some other phenomenon somewhere along the line.

This is actually quite interesting: males with blue eyes have been shown to have a preference for females with blue eyes. This is thought to be an evolutionary adaptation to avoid fathering offspring that aren't yours.

(Literature tend to simplify it for Mendelian genetics as: BB = brown; bb = blue; Bb = brown).
"What are humans if they don't learn at University? Animals, yes."

^^One of my ex-girlfriends said that. I stress the ex part.

j_todorov
Garter
Garter
Posts: 2
Joined: Mon Apr 23, 2007 4:15 pm

Post by j_todorov » Mon Apr 23, 2007 5:50 pm

Thank you very much!!!

Darby
Viper
Viper
Posts: 1278
Joined: Thu Mar 02, 2006 5:29 pm
Location: New York, USA

Post by Darby » Wed Apr 25, 2007 2:45 pm

It is possible if a parent has a brown allele but lacks working color processors. That should be a rare occurrence (but I've run into it).

User avatar
kotoreru
Coral
Coral
Posts: 400
Joined: Thu Apr 12, 2007 9:25 pm
Location: London

Post by kotoreru » Wed Apr 25, 2007 3:33 pm

Darby, do you know of any decent links to sites/papers that explain in detail eye colour heredity etc.? I'd love to know more about this.
"What are humans if they don't learn at University? Animals, yes."

^^One of my ex-girlfriends said that. I stress the ex part.

User avatar
Poison
Inland Taipan
Inland Taipan
Posts: 2322
Joined: Sun Jan 02, 2005 12:44 pm
Location: Turkey

Post by Poison » Sat Apr 28, 2007 8:53 pm

yes that's possible. eye color heredity is a bit complex. Multiple modificator genes play role.
That's rara but yes 2 parets with blue eyes CAN have children with brown eyes.
It matters not how strait the gate
How charged with punishment the scroll
I am the Master of my fate
I am the Captain of my soul.

User avatar
Poison
Inland Taipan
Inland Taipan
Posts: 2322
Joined: Sun Jan 02, 2005 12:44 pm
Location: Turkey

Post by Poison » Sat Apr 28, 2007 9:08 pm

For more info: (university level)
brown color occurance: front layer of iris has melanin
blue color occurance: front layer lack melanin. Back part has it.
Multiple modificator genes are genes that are not alleles of a trait but playes role on phenotypic expression. They affect pigment production, tones etc. (that's how colors other than blue and brown occurs)
Let's say both of the parents have blue eyes. But one of them (or even both of them) can be Bb but because of multiple modificator genes pigment production can be blocked. So his/her eyes appears to be blue. He/She can give that B to his /her child. So the child now carries the dominant allele B. And the eye color is brown.
Hope this helped.
It matters not how strait the gate
How charged with punishment the scroll
I am the Master of my fate
I am the Captain of my soul.

User avatar
MrMistery
Inland Taipan
Inland Taipan
Posts: 6832
Joined: Thu Mar 03, 2005 10:18 pm
Location: Romania(small and unimportant country)
Contact:

Post by MrMistery » Mon Apr 30, 2007 12:34 pm

@ozge
I may be wrong, but from what i remember, if a person has blue eyes he must be recessive for all 3 genes involved. So that would mean it is indeed impossible for the parents with blue eyes to have a brown-eyed child.
"As a biologist, I firmly believe that when you're dead, you're dead. Except for what you live behind in history. That's the only afterlife" - J. Craig Venter

Darby
Viper
Viper
Posts: 1278
Joined: Thu Mar 02, 2006 5:29 pm
Location: New York, USA

Post by Darby » Mon Apr 30, 2007 5:56 pm


User avatar
Poison
Inland Taipan
Inland Taipan
Posts: 2322
Joined: Sun Jan 02, 2005 12:44 pm
Location: Turkey

Post by Poison » Mon Apr 30, 2007 6:05 pm

MrMistery wrote:@ozge
I may be wrong, but from what i remember, if a person has blue eyes he must be recessive for all 3 genes involved. So that would mean it is indeed impossible for the parents with blue eyes to have a brown-eyed child.


Are you sure? I think you are worng. What I wrote is something that is told during our genetic classes. If someone is Bb but melanin production on the front layer is blocked by another gene eyes will appear to be blue. What's more, 2 alleles (brown and blue) and many multiple modificator genes are involved in the heredity of eye color. Some change the tone of the pigment or amount of production. And that's how other colors form.
It matters not how strait the gate
How charged with punishment the scroll
I am the Master of my fate
I am the Captain of my soul.

Post Reply

Who is online

Users browsing this forum: No registered users and 4 guests