Showing posts with label . DNA damage is significantly related to age. Show all posts
Showing posts with label . DNA damage is significantly related to age. Show all posts

Saturday, March 7, 2009

James Watson Co-discoverer of DNA struct understands the connection between being an older father 35 and up and having an offspring with schizophrenia

From The Sunday Times
March 8, 2009
Not too bright? Now the blame is on your old man
Jonathan Leake, Science Editor

CHILDREN with older fathers seem to perform worse in intelligence tests, according to a study due out this week.
They tended to obtain significantly lower scores in a variety of cognitive tests than those born to younger fathers, researchers have found.
The results could be controversial. Until recent years it had been thought that it was a mother’s age that had most impact on the health and abilities of children. The father’s age, by contrast, was thought to be much less important.
The research, led by John McGrath, of the Queensland Brain Institute at the University of Queensland in Australia, suggests such ideas need rethinking.
“The offspring of older fathers show subtle impairments on tests of neurocognitive ability during infancy and childhood,” he said. “In light of the trends to delay fatherhood, the clinical implications and the mechanisms underlying these findings warrant closer scrutiny.”
Other research has shown linkage between advanced paternal age (men over 35) and an increased risk of neurodevelopmental disorders, such as autism and schizophrenia, as well as dyslexia. Such findings prompted James Watson, co-discoverer of the structure of DNA, to speak of his concern. His son Rufus suffers from schizophrenia and as more is uncovered about its causes Watson has publicly questioned if he is to blame. “I worry that I was 42 with Rufus,” he says. “I read that the frequency of schizophrenia goes up with the age of both parents.”
The tests, designed to measure the ability to think and reason, also generated a second startling finding — that children with older mothers gain higher intelligence scores.
McGrath analysed data on 33,437 Americans born between 1959 and 1965. All were tested at eight months, four years and seven. The data set, despite its age, remains one of the best resources. McGrath also used advanced statistical techniques to remove environmental influences.
For McGrath one of the key questions is the underlying biological mechanisms. One idea is that as men age the cells that produce sperm suffer increasing numbers of mutations, which are passed on to an offspring.
Why, though, would children born to older mothers tend to have higher intelligence? McGrath suggests this is because women’s eggs are formed when they are still in the womb and so their DNA is protected from mutation until they are used.

Tuesday, November 25, 2008

. DNA damage is significantly related to age

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Sperm DNA Damage: Correlation To Severity Of Semen Abnormalities
Main Category: Fertility
Also Included In: Urology / Nephrology; Genetics
Article Date: 24 Nov 2008 - 1:00 PST

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SAN FRANCISCO, CA, USA (UroToday.com) - Evaluation of male fertility includes assessment of the standard semen parameters (SSP) and may include assessment of DNA damage. However, the relationship between DNA damage and SSP remains controversial. This study examined the the relationship of DNA damage to SSP in patients presenting for infertility evaluation.

The authors conducted an IRB approved retrospective review of semen samples from 2586 unselected non-azoospermic patients underwent computer-assisted semen analysis and flow cytometry based sperm DNA damage assessment expressed as the DNA Fragmentation Index (DFI). DFI was significantly negatively correlated to sperm concentration, motility, and normal morphology and positively correlated to age (P<0.001). DNA damage increased in relationship to the number of abnormalities in the SSP (P <0.001).

The authors concluded:

1. DNA damage is significantly related to standard parameters of semen analysis
2. DNA damage is significantly related to age
3. The degree of DNA damage increases with the number of abnormal parameters in a sample and is most severe in patients with oligo-astheno-teratospermia (OAT).

Editorial Comments:

The authors demonstrate the relationship between progressively more abnormal semen parameters and abnormal DFI. This is consistent with clinical observations and does not appear to demonstrate any incremental value to DFI assessment, in clinical practice, in the initial assessment of the infertile male.

Presented by S. I. Moskovtsev, J. Willis, and J. White, et al., at the 64th Annual Meeting of the American Society for Reproductive Medicine - November 8 - 12, 2008 - San Francisco, California

Reported by UroToday.com Contributing Editor Harris M. Nagler, MD

UroToday - the only urology website with original content written by global urology key opinion leaders actively engaged in clinical practice.

To access the latest urology news releases from UroToday, go to: www.urotoday.com





Sperm DNA Damage Linked To Increased Risk of Pregnancy Loss after IVF and ICSI
November 25, 2008
Earlier studies have indicated that spermatozoa of infertile men possess considerably more sperm DNA damage than that of fertile men, which could adversely affect both natural reproduction and assisted reproduction technology (ART) outcomes. Since the use of ART to treat infertility has increased substantially from its introduction in the US, in 1981, there is a huge concern regarding the safety of using DNA-damaged spermatozoa. Now, a recent study published online in the journal, Human Reproduction, demonstrates that sperm DNA damage is associated with a significantly enhanced risk of pregnancy loss following in vitro fertilization (IVF) and intra cytoplasmic sperm injection (ICSI).