The timing of monozygotic twinning: a criticism of the common model

@article{Herranz2013TheTO,
  title={The timing of monozygotic twinning: a criticism of the common model},
  author={Gonzalo Herranz},
  journal={Zygote},
  year={2013},
  volume={23},
  pages={27 - 40}
}
Summary In the dominant model, monozygotic (MZ) twinning is universally accepted as a post-fertilization event resulting from splitting of the embryo along its first 2 weeks of development. The stage at which splitting occurs determines chorionicity and amnionicity. A short history on how the model was built is presented, stressing the role played by some embryologists, in particular George Corner, in its completion and final success. Strikingly, for more than 60 years no deep criticisms have… 

Response: The timing of monozygotic twinning: a pro-life challenge to conventional scientific wisdom.

  • G. Herranz
  • Biology
    Reproductive biomedicine online
  • 2014

Comment on G. Herranz: The timing of monozygotic twinning: a criticism of the common model. Zygote (2013)

The topic of monozygotic twinning (MT) on which the recent paper by Herranz (Herranz, 2013) focuses is indeed a fascinating one, but when reading through the paper, however, I have ended up disappointed.

On the origin of zygosity and chorionicity in twinning: evidence from human in vitro fertilization

The current knowledge is documented, the accepted dogma is criticized, and new insights are proposed into the origin of zygosity and chorionicity are proposed.

The timing of monozygotic twinning: a pro-life challenge to conventional scientific wisdom.

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While the evidence for bias due to chorionicity was mixed or null for many outcomes, results do, however, consistently suggest that heritability estimates are underestimated for measures of birth weight and early growth when chorions/placentas are not taken into account.

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