Navigation Links
Dad's Genes May Play Greater Role Than Thought
Date:6/15/2009

Data on 'packaging' in sperm cells may also help assess infertility,,

MONDAY, June 15 (HealthDay News) -- Biologists say they have discovered a clever packaging scheme that allows the genetic material in sperm to have far more influence over development of a fertilized egg than had been imagined.

The discovery has potential applications in helping infertile men, said Brad Cairns, a professor of oncological sciences at the University of Utah and a leader of the team reporting the finding in the June 14 online edition of Nature.

The vast majority of the DNA molecules that carry genetic information are tightly packaged in sperm cells, Cairns said. That tight packaging enables a win in what is literally a race for life because the first sperm to reach an egg fertilizes it, and the tightest packages are the most streamlined.

"But when it comes to development, the sperm is at a real disadvantage," Cairns said. "The vast majority of their genes are tightly packed in material that is not helpful in giving them full expression."

In every cell other than sperm, DNA molecules are wrapped around structures called histones, an arrangement that allows for easy transmission of their genetic instructions. But only 4 percent of sperm DNA is arranged around histones. The other 96 percent is in a dense, impenetrable material called protamine.

"The hypothesis has been that this 4 percent of DNA in histones is randomly distributed," Cairns said. "We challenged the hypothesis and found that the DNA that is in histones is not randomly distributed but is located at important genes for embryonic development."

The discovery was made by using DNA from sperm at the University of Utah's in vitro fertilization clinic. "We isolated the DNA attached to histones and sequenced it," Cairns said. "We found genes that are important in guiding the development of the embryo."

The discovery raises "obvious questions" about the importance of DNA packaging in sperm on human fertility, he said.

"Do infertile men have problems in packaging, and is that the basis of their problem?" Cairns asked. "We already have preliminary evidence that the majority of infertile men have problems in gene packaging. There is an incorrect ratio of histones to protamine."

Cairns said that the gene packaging issue is related to another biological aspect of DNA expression -- DNA methylation. Some subunits of the DNA molecules ordinarily have molecules called methyl groups attached to them. Lack of methylation can also contribute to infertility, he said.

The Utah group is working on a test that could define the root issues in men with fertility problems, Cairns said. "We are working toward a clinical diagnostic test for infertile men that would assess their packaging and DNA methylation status so that we could counsel them on whether they can have success in achieving fertility," he said.

The concept of possible intervention to improve fertility is much more distant, he said.

From the basic science point of view, one major lesson of the discovery is that DNA is not the only molecule that can carry genetic information from generation to generation, said William G. Kelly, an associate professor of biology at Emory University, whose review article will appear in the same issue of the journal.

What the study shows "is that the histones still sitting there have really important information that actually guides the genes that regulate early events in the development of the next generation," Kelly said.

That idea has been proposed, but "it was not clear that this information could survive the packaging in sperm," he said.

"This firmly shows that information that's there can be information that is passed across generations and that is not encoded in DNA," Kelly said.

More information

The Yale Fertility Center has more on the causes and treatment of infertility.



SOURCES: Bradley Cairns, Ph.D., professor, oncological sciences, University of Utah, Salt Lake City; William G. Kelly, Ph.D., associate professor, biology, Emory University, Atlanta; June 14, 2009, Nature, online


'/>"/>
Copyright©2009 ScoutNews,LLC.
All rights reserved  

Related medicine news :

1. Parents of Murdered Dating Violence Victim, Legislators, and Teachers Unite to Launch MADE - Moms and Dads for Education to Stop Teen Dating Abuse
2. Bounty Launches New Survival Guide Website for Dads
3. Massage Chairs Promote Comfort and Happy Dads for Fathers Day
4. Fathers Day is Almost Here: Two Pediatric Nurses, Moms, Offer Practical Guidebook & DVD for New Dads
5. Dads Early-Onset Obesity Linked to Liver Disease in Kids
6. Dads Substance Use Hurts Expectant Moms Efforts to Quit
7. Some moms quit cigarettes, marijuana, alcohol during pregnancy, but dads dont
8. Dads break bones of children more often than moms
9. Having Lots of Kids Helps Dads Live to 100
10. A breakthrough in gastric carcinogenesis
11. Innovative New Wellness and Nutrition Program Leverages Latest Understanding of Relationship Between Diet and Genes
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Dad's Genes May Play Greater Role Than Thought
(Date:10/13/2017)... Pekin, IL (PRWEB) , ... October 13, 2017 ... ... Foundation, which established the certification process to promote standards of excellence for the ... iaedp™ Symposium, scheduled for March 22 – 25, 2018 in Orlando, Florida at ...
(Date:10/13/2017)... ... ... Lori R. Somekh, founder of the Law Office of Somekh & Associates ... special needs planning attorneys. “Membership in ElderCounsel helps our office remain up to date ... elder law attorneys nationwide,” said Somekh. , ElderCounsel was founded by ...
(Date:10/13/2017)... RIDGE, N.J. (PRWEB) , ... October 13, 2017 , ... ... annual Holly Day Market. Featuring a collection of specialty vendors and unique items from ... of personalized and quality-focused health and wellness services offered by the VNA. The ...
(Date:10/13/2017)... ... 2017 , ... Yisrayl Hawkins, Pastor and Overseer at The House of Yahweh, ... and least understood books in the Holy Scriptures, Revelation. The Book of Revelation paints ... for centuries. Many have tossed it off as mere rubbish, but Yisrayl Hawkins says ...
(Date:10/13/2017)... ... 13, 2017 , ... “The Journey: From the Mountains to the Mission Field”: ... souls in the Philippines. “The Journey: From the Mountains to the Mission Field” is ... Bible. She has taught all ages and currently teaches a class of ladies at ...
Breaking Medicine News(10 mins):
(Date:9/27/2017)... 27, 2017  Commended for their devotion to personalized service, ... as number one in the South Florida Business Journal,s 50 ... 5000 yearly list, the national specialty pharmacy has found its ... will soon be honored by SFBJ as the 2017 ... Set to receive his award in October, Bardisa said ...
(Date:9/23/2017)... -- Janssen Biotech, Inc. (Janssen) announced today that it ... Food and Drug Administration (FDA) for the Biologics License ... of moderately to severely active rheumatoid arthritis (RA). The ... to further evaluate the safety of sirukumab in the ... "We are disappointed by ...
(Date:9/19/2017)... Sept. 19, 2017   ZirMed Inc ., a recognized ... announced that it has been ranked #1 by its users ... Rankings 2017 User Survey. ZirMed was recognized as the ... hospitals and medical centers over 200 beds and holds one ... technology user survey history. ...
Breaking Medicine Technology: