Monday, May 28, 2007


You can be too old to be a dad!
By Akintayo Abodunrin

An old couple

It is believed that age has very little effect on men as it pertains to fertility. But it has now been revealed that men who think age has no effect on their fertility need to have a rethink as emerging scientific facts suggest otherwise. Akintayo Abodunrin reports.


Minding Your Mind

New Key to Autism

September 25, 2006

By Michael Craig Miller, M.D.
Harvard Medical School

Convincing Evidence
What Causes These Genetic Errors?
Should Older Men Stop Fathering Babies?
A study published in the September, 2006 issue of the Archives of General Psychiatry may give older prospective fathers pause before plunging into biological parenthood. The authors found a significant increase in the risk of autism and similar disorders as fathers got older.

What Is Autism?
Autism is a profoundly disabling disorder that starts in early childhood. The key features are:

Abnormal social development – little or no eye contact, prefers to be alone
Difficulty communicating – impaired language ability, uses gestures or pointing rather than words
Unusual behavior – spins objects, doesn't like being cuddled
Evidence of strong abilities sometimes in non-verbal areas, such as math or music
Older people with autism may have some ability to interact with people, but about two-thirds are mentally retarded and most cannot live on their own
Unfortunately, the incidence of this illness appears to be on the rise. Some experts think autism is diagnosed more often simply because more people are aware of it. But that's probably not the whole explanation.

Genetic factors almost certainly play a big role. So autism researchers are eager to discover anything that might increase a person's genetic vulnerability, such as delaying parenthood until age 40 or beyond.

The risk was smallest for children of fathers younger than 20 and greatest for children of fathers older than 50. A man in his 40s, for example, was almost 6 times as likely to have an autistic child as a man age 20. This relationship held even after researchers adjusted the results for the year of the person's birth, their socioeconomic status, or the mother’s age.

This is not the first discovery of its type. Healthcare professionals have long known that as parents age, the risk of giving birth to a child with certain illnesses goes up. Older mothers, for example, are more likely to have a child with Down syndrome. In recent years, studies have revealed a link between aging fathers and schizophrenia.

Convincing Evidence

The Archives study took advantage of the extraordinarily complete health records of over 300,000 Israeli men and women who underwent a complete health assessment when they were 17-year olds — draft age. This gave researchers a good way to determine the incidence of autism in the population. The researchers had access to intellectual, medical and psychiatric evaluations of almost all Israeli boys and three-quarters of girls. (Their identities were kept secret, however.) For most individuals, the father’s age at birth was known.


: Mol Psychiatry. 2007 May;12(5):419-421.Paternal age and autism are associated in a family-based sample.Cantor RM, Yoon JL, Furr J, Lajonchere CM.
[1] 1Department of Human Genetics, David Geffen School of Medicine at University of California at Los Angeles, Los Angeles, CA, USA [2] 2Department of Pediatrics, David Geffen School of Medicine at University of California at Los Angeles, Los Angeles, CA, USA [3] 3AGRE Consortium, Los Angeles, CA, USA.

PMID: 17453057 [PubMed - as supplied by publisher]

The paternal age distribution of the AGRE fathers, whose first child is autistic differs significantly from that of the 'control' sample (P=0.005). A 2 goodness-of-fit test with 2 degrees of freedom was conducted using percents in the 'control' group age categories to calculate the expected values in the AGRE sample. The shift toward higher paternal ages in those with an affected first-born is seen most dramatically in the group of AGRE fathers who are 30–39 years inclusive, which is 54.7% of the distribution compared with the 41.9 % that is expected. We interpret this shifted age distribution to provide support for the recently reported finding by Reichenberg and co-workers that autism risk is associated with advancing paternal age.
Labels: CM Lajonchere, J Furr, JL Yoon, RM Cantor

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