Patterson Fails To Mention Increasing Paternal Age At The Time of Conception is Responsible For At Least Half of Schizophrenia and Autism How Typical
Dr. Patterson neglects a robust risk factor responsible for up one third and maybe by now more than one third of all cases.
Dolores Malaspina M.D. Chair of N.Y.U. Department of Psychiatry:
"What is the most irrefutable finding that you and your colleagues have made?"
"The most irrefutable finding is our demonstration that a father’s age is a major risk factor for schizophrenia. We were the first group to show that schizophrenia is linearly related to paternal age and that the risk is tripled for the offspring of the oldest groups of fathers.7 This finding has been born out in every single cohort study that has looked at paternal age and the risk for schizophrenia. The only other finding that has been as consistently replicated in schizophrenia research is that there is an increased risk associated with a family history of schizophrenia. Since only 10% to 15% of schizophrenia cases have a family history, family history does not explain much of the population risk for schizophrenia. However, we think that approximately one third or one quarter of all schizophrenia cases may be attributable to paternal age. Paternal age is the major source of de novo genetic diseases in the human population, which was first described by Penrose8 in the 1950s. He hypothesized that this was due to copy errors that arose in the male germ line over the many cycles of sperm cell replications. These mutations accumulate as paternal age advances. After the Penrose report, medical researchers identified scores of sporadic diseases in the offspring of older fathers, suggesting that these could occur from gene mutations. Particular attention was paid to conditions in last-born children. In the 1960s, an excess of schizophrenia in last-born children was also reported......"
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Mother's flu could lead to mental illnessesBy Stephen Lunn
July 16, 2007 12:00am
WOMEN who catch the flu during pregnancy are up to seven times more likely to have a child with schizophrenia - and scientists believe they have finally figured out why.
A rogue protein, interleukin 6 - produced when a pregnant woman is fighting a viral infection - may help trigger mental illnesses such as autism and schizophrenia in the child, US neuroscientist Paul Patterson said yesterday.
Professor Patterson, speaking from an international neuroscience conference in Melbourne, said schizophrenia and autism resulted from a combination of environmental factors such as the mother's health and genetic predisposition.
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Fathers’ Age as Contributor to Risk for Autism
Filed under: Uncategorized — JohnL @ 8:03 am
Fathers’ Age as Contributor to Risk for Autism
Leslie Feldman
The average age of fatherhood is increasing in the US and in Western Europe. Some research shows that offspring of older fathers are at increased risk for diseases and conditions (Bray et al., 2006). Some experts predict an upswing in cases of schizophrenia will accompany the increasing average paternal age. “The actual percentage of cases with paternal germ line-derived schizophrenia in a given population will depend on the demographics of paternal childbearing age, among other factors. With an upswing in paternal age, these cases would be expected to become more prevalent” (Malaspina et al., 2006). Approximately 25-33% of all cases of schizophrenia may be due to the father’s age at conception, according to Malaspina (2006). Malaspina sees a connection between advancing paternal age and neural functioning difficulties in people with autism and with schizophrenia. According to Tarin et al. (1998), there are well over 30 known conditions that the offspring of older fathers are more at risk for (see chart on paternal aging in the linked article).
The diagnosis of autism is increasing in the US and elsewhere (Centers for Disease Control, 2006). In a population study of 1990 through 1999, a total of 669,995 children, Atladóttir and colleagues (2007) reported increased diagnosese of autism, Torrette Syndrome, and hyperkinetic disorder. Is there a connection between increased cases of disorders such as autism and increased average paternal age? Psychiatrist Michael Craig Miller (2006), editor of the Harvard Mental Health Letter is convinced there is. Although a connection between the two would be corelational (not causal), the relationship encourages examination of the possibility that something related to paternal age (e.g. mutations in gametes) may contribute to the occurrence of autism. If there is a potential causal relationship, the new study by the Centers for Autism and Developmental Disabilities Research and Epidemiology (CADDRE) Network would provide a valuable opportunity to test the hypothesis.
Observations of a connection between advanced paternal age and difficulties for offspring go way back. Earlier research looking for a link between maternal age and autism also found the average paternal age (34) was much higher than the average age in the general population (Gillberg, 1980). Geneticist James F. Crow (1997) cites Wilhelm Weinberg (1862-1937) as noticing, during his 42 years of medical practice and helping 3,500 births, that the mutation rate might be a function of paternal age. Crow said, the evidence suggested that the greatest mutational health hazard in the population is fertile old men.
A study by Reichenberg et al. (2006) found a strong connection between cases of autism and advancing paternal age. Reichenberg and colleagues, who found more autism as paternal age increased, also found that the ratio of girls to boys in this cohort was 1:1, suggesting that this was a special subset of autism, maybe de novo rather than familial autism.
What might be the mechanism that produces higher rates of disorders among children of older fathers? The DNA in a 20 year-old male has been copied approximately100 times but in a 50 year-old father it has been copied over 800 times. Singh and colleagues (2003) studied differences in the sperm of older and younger men. Men over age 35 have sperm with lower motility and more highly damaged DNA in the form of double-strand breaks. The older group also had fewer apoptotic cells, an important discovery. (Apoptosis is form of cell death that protects the parent organism from problems or that permits differentiation, as in resorption of a tadpole’s tail.) A really key factor that differentiates sperm from other cells in the body is that they do not repair their DNA damage, as most other cells do. As a result, the only way to avoid passing DNA damage to a child is for the damaged cells to undergo apoptosis, a process that the study indicates declines with age. Singh is quoted in Science Blog (Sullivan, 2002) as explaining that, “In older men, the sperm are accumulating more damage, and those severely damaged sperm are not being eliminated.”
Sources
The following list of sources is for works cited in this document or for other studies finding a connection between age of fathers at conception and various disorders. Access to some of the Web-based resources may be limited because of the policies of the publishers.
Atladóttir, H. O., Parner, E. T., Schendel, D., Dalsgaard, S., Thomsen, P. H., & Thorsen, P. (2007). Time trends in reported diagnoses of childhood neuropsychiatric disorders. Arch Pediatr Adolesc Med., 161, 193-198. Link
Brown et al. (2002): Paternal age and risk of schizophrenia in adult offspring. Am J Psychiatry, 159, 1528-1533. Link
Bray, I., Gunnell, D., & Smith, G. D. (2006). Advanced paternal age: How old is too old? Journal of Epidemiology and Community Health, 60, 851-853. Link
Burd et al., (1999). Prenatal and perinatal risk factors for autism. J. Perinatal. Med., 27, 441-450. Link
Byrne, M., Agerbo, E., Ewald, H., Easton, W. W., & Mortensen, P. D. (2003). Parental age and risk of schizophrenia, A case control study. Arch Gen Psychiatry, 60, 673-678. Link
Centers for Disease Control, (2006). How common are Autism Spectrum Disorders (ASD)? Link
Centers for Disease Control. (2002). Prevalence of the Autism Spectrum Disorders (ASDs) in multiple areas of the United States, 2000 and 2002. Atlanta, GA: Author. Link
Crow, J. F. (1997). The high spontaneous mutation rate: Is it a health risk? Proc. Natl. Acad. Sci. USA, 94, 8380-8386. Link
Dalman, C., & Allebeck, D. (2002). Paternal age and schizophrenia: Further support for an association. Am J Psychiatry, 159, 1591-1592. Link
Gillberg, C. (1980). Maternal age and infantile autism. J. Autism and Developmental Disorders, 10, 293-297. Link
Lauritsen M. B., Pedersen, C. B., & Mortensen, P. B. (2005) Effect of familial risk factors and place of birth on the risk of autism: a nationwide register-based study. J. Child Psychology and Psychiatry, 46, 963-971. Link
Miller, M. C. (2006) A new key to Autism. Aetna IntelliHealth, September 25. Link
Malaspina, D., et al. (2001): Advancing paternal age and the risk of schizophrenia. Arch Gen Psychiatry, 58, 361-367. Link
Malaspina, D. (2006). In session with Dolores Malaspina, MD, MSPH: Impact of childhood trauma on psychiatric illness (interview by N. Sussman). Primary Psychiatry, 13(7), 33-36. Link
Malaspina, D. (2006). Schizophrenia risk and the paternal germ line. Schizophrenia Research Forum. Link
Rasmussen, F. (2006) Paternal age, size at birth, size in young adulthood&mdashrisk factors for schizophrenia. Eur Journal of Endocrinology, 155 Suppl 1:S65-69. Link
Reichenburg, A., Gross, R., Weiser, M. Bresnahan, M., Silverman, J. Harlap, S., et al. (2006). Advancing paternal age and autism. Arch Gen Psychiatry, 63, 1026-1032. Link
Singh, N. P., Muller, C. H., & Burger, R. E. (2003). Effects of age on DNA double-strand breaks and apoptosis in human sperm. Fertility and Sterility, 80, 1420-1430. Link
Sipos, A., Rasmussen, R., Harrison, G., Tynelius, P., Lews, G., Leon, D. A., et al. (2004). Paternal age and schizophrenia: A population based cohort study. BMJ, 329, 1070. Link
Sullivan, B. J. (2002). Research reveals a cellular basis for a male biological clock. Science Blog, 2002-11-25 22:31. Link
Tarin, J. J., Brines, J., & Cano, A. (1998). Long-term effects of delayed parenthood. Human Reproduction, 13, 2371-2376. Link
Tsuchiya, K. J., Takagai, S., Kawai, M., Matsumoto, H., Nakamura, K., Minabe, Y., et al. (2005). Advanced paternal age associated with an elevated risk for schizophrenia in offspring in a Japanese population. Schizophrenia Research, 76, 337-342. Link
Wohl, M. & Gorwood, P. (2006). Paternal ages below or above 35 are associated with a different risk for schizophrenia in offspring. Eur. Psychiatry, Dec 1 [Epub ahead of print]. Link
Zammit, S., Allebeck, P., Dalman, C., Lundgerg, I., Hemming, T., Owen, M. J., et al. (2003). Paternal age and risk for schizophrenia. Br. J. Psychiatry, 183, 405-408. Link
Labels: Paul Patterson leaves out paternal age and schizophrenia and autism risk
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