News

2013.06.19 Press Release

The influence of interaction between genetic and environmental factors on the ultrasonic distress vocalizations in mice: The first clue to elucidate the mechanism on risk of autism related to the age of father and in vitro fertilization

Recently, the marked increase in the incidence of autism has become a social problem in developed countries. In epidemiological studies conducted, the increase in the incidence of cases of autism in children has been reported with older fathers and in vitro fertilization (IVF). In addition, a possibility has been pointed out that PAX6 (paired box protein 6), known as an important factor in brain development, is involved in the incidence of autism.

Professor Noriko Osumi's group at the Graduate School of Medicine at Tohoku University focused on ultrasonic distress vocalizations (USV) that is used as an index of autism-like symptoms in mice and established that the older age of the father increased the incidence of autism-like symptoms in the offspring. In comparing the number of USV calls measured for 5 minutes from 6 day old mouse pups separated from their mothers, the pups with older wild type father mice aged 12 months or more showed a significant reduction in the number of USV calls than from the pups with young 3 month old wild type father mice.

Next, the group examined the correlation between the Pax6 gene mutation and aging. In the offspring of 3 month old Pax6 mutant father mice, the number of USV calls from the mutant pups did not change compared to the wild type pups, but the number of USV calls from the Pax6 mutant pups was dramatically reduced compared from their wild type littermates derived from 6-8 month old Pax6 mutant father mice. Also when investigating the influence of Pax6 gene mutation and IVF, the USV calls of the Pax6 mutant pups derived from the younger, 3 month old Pax6 mutant father mice was significantly reduced compared to the wild type offspring derived from the Pax6 mutant father mice.

From a biological standpoint, the aging of the father increases the risk of developing autism in their children, and a genetic risk can be confound by environmental conditions such as IVF and paternal aging. In the future, further developments in elucidating the relationship between the parents’ environment and genetic factors affecting the offspring can be made through analyzing the epigenetic changes during spermatogenesis. We expect that the mechanism related to the risk of suffering from autism will be elucidated through analyzing the epigenetic changes affecting the number of the USV calls in mouse pups.

The research results will be presented at Neuro 2013 on June 22, 2013 at Kyoto.

[Contact]
(About the research)
Professor Noriko Osumi
Division of Developmental Neuroscience
Tohoku University Graduate School of Medicine
TEL: +81-22-717-8203
E-mail: osumi*med.tohoku.ac.jp (Replace * with @)

(Public Relations)
Lecturer Hitoshi Inada
Public Relations Office of Tohoku University Graduate School of Medicine
TEL: +81-22-717-7891
FAX: +81-22-717-8187
E-mail: pr-office*med.tohoku.ac.jp (Replace * with @)