University of Virginia, Charlottsville, VA 22908, USA.
Reprod Biomed Online. 2010 May;20(5):660-3. doi: 10.1016/j.rbmo.2010.01.011. Epub 2010 Feb 1.
The objective of this study was to investigate whether skewed X chromosome inactivation (XCI) is associated with IVF. A retrospective cohort study was performed comprising 30 female infants conceived by IVF and 44 naturally conceived control infants matched for gestational age and sex. Cord blood DNA samples were obtained and XCI patterns were analysed using a methylation-sensitive assay. Eight IVF samples and 13 control samples were excluded from the study because they were either homozygous or alleles were too similar for the assay to determine skewing. Mildly skewed XCI (80-90% inactivation of one allele) was present in two of 22 (9.1%) IVF samples and two of 31 (6.5%) control samples. Extremely skewed XCI (>90% inactivation of one allele) was found in two of 22 (9.1%) IVF samples and none of 31 control samples. Neither difference was statistically significant. However, the mean degree of skewed XCI in the IVF group was 72.0% and in the control group was 62.4% (P=0.002). Larger studies are needed to clarify the relationship between IVF and skewed XCI.
本研究旨在探讨偏置性 X 染色体失活（XCI）是否与体外受精（IVF）有关。进行了一项回顾性队列研究，纳入了 30 名通过 IVF 受孕的女性婴儿和 44 名性别和胎龄相匹配的自然受孕对照婴儿。采集脐血 DNA 样本，并用甲基化敏感检测分析 XCI 模式。由于 8 个 IVF 样本和 13 个对照样本要么是纯合子，要么等位基因太相似，无法确定偏倚，因此这些样本被排除在研究之外。在 22 个 IVF 样本中有 2 个（9.1%）和 31 个对照样本中有 2 个（6.5%）存在轻度偏置 XCI（一个等位基因的失活率为 80-90%）。在 22 个 IVF 样本中有 2 个（9.1%）和 31 个对照样本中没有一个（0%）存在极度偏置 XCI（一个等位基因的失活率>90%）。但这些差异均无统计学意义。然而，IVF 组的平均偏置 XCI 程度为 72.0%，对照组为 62.4%（P=0.002）。需要更大的研究来阐明 IVF 和偏置 XCI 之间的关系。
