Record Display for the EPA National Library CatalogRECORD NUMBER: 1 OF 1
|Main Title||Maternal Age Effect: The Enigma of Down Syndrome and Other Trisomic Conditions.|
|Author||Gaulden, M. E. ;|
|CORP Author||Texas Univ. Southwestern Medical Center at Dallas. Dept. of Radiology.;Environmental Protection Agency, Washington, DC. Office of Health and Environmental Assessment.|
|Report Number||EPA/600/J-93/175 ; OHEA-R-478|
|Additional Subjects||Maternal age ; Down syndrome ; Trisomy ; Aneuploidy ; Genetic nondisjunction ; Hormones ; Regional blood flow ; Oxygen ; Carbon dioxide ; Graafian follicle ; Oocytes ; Genetic recombination ; Mutations ; Reprints ; Female genetic risk|
Aneuploidy is the most frequently observed chromosome abnormality in human liveborn, abortuses, and oocytes. The only etiological factor that has been established is advanced maternal age for the occurrence of trisomies, particularly trisomy 21 which causes Down syndrome. The maternal age effect remains an enigma. Recent molecular data bearing on this question are reviewed as are the hypotheses that have been proposed linking nondisjunction and maternal age. Rationale is presented for a compromised microcirculation hypothesis that explains the cause of nondisjunction and why its occurrence changes with maternal age. The hypothesis proposes that aneuploid oocytes arise from a concatenation of events.