X-chromosome inactivation in female newborns conceived by assisted reproductive technologies
Elizabeth X Wu1, Paloma Stanar1, Sai Ma1
1Department of Obstetrics and Gynaecology, University of British Columbia, Vancouver, British Columbia, Canada.
Objective:
To investigate X-chromosome inactivation (XCI) skewing in female newborns conceived by intracytoplasmic sperm injection (ICSI), in vitro fertilization (IVF), and naturally.
Design:
Case-control study.
Setting:
Research institution.
Patient(S):
A total of 185 female newborns, including 60 conceived by intracytoplasmic sperm injection (ICSI), 73 by in vitro fertilization (IVF), and 52 naturally conceived (NC).
Intervention(S):
DNA was extracted from umbilical cord blood after birth.
Main Outcome Measure(S):
XCI skewing values determined by assaying allelic ratio of methylated alleles at the androgen receptor (AR), fragile X mental retardation 1 (FMR1), and DXS6673E loci.
Result(S):
In the comparison of the ICSI, IVF, and NC populations, the frequency of skewing ≥ 75% (7.0% vs. 5.7% vs. 2.0%, respectively) or ≥ 90% (0 vs. 1.4% vs. 2.0%, respectively) was not statistically significantly different. The mean level of skewing between the ICSI, IVF, and NC groups also did not differ (63.7% vs. 61.8% vs. 60.7%, respectively). Skewing variability was observed in the placentas of the two extremely skewed cases. The parental origin of the preferentially inactivated X chromosome in the extremely skewed IVF and NC cases were maternal and paternal, respectively.
Conclusion(S):
The assisted reproductive technologies of ICSI and IVF do not appear to affect XCI skewing. Skewing variability within the placentas analyzed supports the theory that weaker selective pressures occur in the placenta that could result in skewed inactivation. Our study is the largest to date to investigate this epigenetic phenomenon in infants conceived by ICSI and IVF alongside age-matched NC controls.
More Related Videos
08:27A Non-random Mouse Model for Pharmacological Reactivation of Mecp2 on the Inactive X Chromosome
Published on: May 22, 2019
08:26Transcriptional Analysis by Nascent RNA FISH of In Vivo Trophoblast Giant Cells or In Vitro Short-term Cultures of Ectoplacental Cone Explants
Published on: August 31, 2016
Related Concept Videos
01:58X-Inactivation
01:58X-inactivation
03:17Inheritance of Chromatin Structures
02:50Dosage Compensation
In addition to sexual development, the X chromosome has genes involved in autosomal functions such as brain development and the immune system. Therefore, males and females with distinct numbers of X chromosomes will...
02:45The Ratio of X Chromosome to Autosomes
Normal male Drosophila has a ratio of one X chromosome to two sets of autosomes. In contrast, normal female...
01:19X-linked Traits