Detection of Mosaicism in amniotic fluid cultures: A CYT02000 collaborative study

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Purpose: To evaluate the assumptions on which the American College of Medical Genetics (ACMG) Standards and Guidelines for detecting mosaicism in amniotic fluid cultures are based.

Methods: Data from 653 cases of amniotic fluid mosaicism were collected from 26 laboratories. A chi-square goodness-of-fit test was used to compare the observed number of mosaic cases with the expected number based on binomial distribution theory.

Results: Comparison of observed data from the in situ colony cases with the expected distribution of cases detected based on the binomial distribution did not reveal a significant difference (P = 0.525).

Conclusions: The empirical data fit the binomial distribution. Therefore, binomial theory can be used as an initial discussion point for determining whether ACMG Standards and Guidelines are adequate for detecting mosaicism.

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Correspondence to Andrew T L. Chen.

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  • prenatal diagnosis
  • cytogenetics
  • chromosomal mosaicism
  • guidelines
  • binomial distribution

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