Abstract
It is tempting to assume that the maternal age effect in trisomy 21 is confined to cases arising from errors of maternal gametogenesis. However, it has been suggested that this hypothesis is incompatible with the results of studies, based on the subjective assessment of chromosome polymorphisms, of the parental origin of the additional chromosome. Contrary to the hypothesis, these studies appear to indicate that the ratio of maternal to paternal errors does not depend significantly on maternal age. I show here that the hypothesis need not be rejected if the proportion of published parental assignments that are incorrect is greater than or equal to 8%, a figure regarded as realistic by some experienced cytogeneticists.
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Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Aymé S., Lippman-Hand A. Maternal-age effect in aneuploidy: does altered embryonic selection play a role? Am J Hum Genet. 1982 Jul;34(4):558–565. [PMC free article] [PubMed] [Google Scholar]
- Carothers A. D. Evidence that altered embryonic selection contributes to maternal-age effect in aneuploidy: a spurious conclusion attributable to pooling of heterogeneous data? Am J Hum Genet. 1983 Sep;35(5):1057–1059. [PMC free article] [PubMed] [Google Scholar]
- Erickson J. D. Down syndrome, paternal age, maternal age and birth order. Ann Hum Genet. 1978 Jan;41(3):289–298. doi: 10.1111/j.1469-1809.1978.tb01896.x. [DOI] [PubMed] [Google Scholar]
- Hook E. B. Maternal age, paternal age, and human chromosome abnormality: nature, magnitude, etiology, and mechanisms of effects. Basic Life Sci. 1985;36:117–132. doi: 10.1007/978-1-4613-2127-9_8. [DOI] [PubMed] [Google Scholar]
- Stein Z., Stein W., Susser M. Attrition of trisomies as a maternal screening device. An explanation of the association of trisomy 21 with maternal age. Lancet. 1986 Apr 26;1(8487):944–947. doi: 10.1016/s0140-6736(86)91046-9. [DOI] [PubMed] [Google Scholar]
- Warburton D., Stein Z., Kline J. In utero selection against fetuses with trisomy. Am J Hum Genet. 1983 Sep;35(5):1059–1064. [PMC free article] [PubMed] [Google Scholar]