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Maternal age effect on the development of Prader-Willi syndrome resulting from upd(15)mat through meiosis 1 errors

Keiko Matsubara1, Nobuyuki Murakami, Toshiro Nagai

  • 1Department of Molecular Endocrinology, National Research Institute for Child Health and Development, 2-10-1 Ohkura, Setagaya, Tokyo, Japan.

Journal of Human Genetics
|June 3, 2011
PubMed

Insights

Advanced maternal age increases the risk of Prader-Willi syndrome (PWS) due to errors during maternal meiosis 1 (M1). This study links delayed childbearing in Japan to a higher incidence of PWS caused by M1 non-disjunction.

Area of Science:

  • Genetics
  • Reproductive Biology
  • Pediatric Disorders

Background:

  • Prader-Willi syndrome (PWS) is a complex genetic disorder.
  • PWS is typically caused by deletions in chromosome 15q11.2-q13 or maternal uniparental disomy (upd(15)mat).
  • Mechanisms for upd(15)mat include trisomy rescue (TR) and gamete complementation (GC), often involving errors in maternal meiosis (M1 or M2).

Purpose of the Study:

  • To investigate the relationship between maternal age and the genetic causes of PWS.
  • To determine if maternal age influences the specific mechanism leading to upd(15)mat.
  • To assess the impact of delayed childbearing trends on PWS incidence.

Main Methods:

  • Analysis of genetic data from 117 Japanese PWS patients.
  • Categorization of patients into deletion and upd(15)mat groups.
  • Statistical comparison of maternal ages between patient groups and across birth cohorts.

Main Results:

  • Maternal age was significantly higher in patients with upd(15)mat resulting from M1 non-disjunction compared to those with deletions.
  • The relative frequency of upd(15)mat from M1 errors increased in patients born after 2003, coinciding with delayed childbearing trends in Japan.
  • M1 non-disjunction, a maternal age-dependent event, was identified as a key factor in upd(15)mat development.

Conclusions:

  • Advanced maternal age is a significant predisposing factor for upd(15)mat in PWS.
  • Increased M1 errors in older mothers contribute to the development of PWS.
  • Delayed childbearing trends may lead to a higher prevalence of PWS cases caused by specific meiotic errors.

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