Specific epigenetic alterations of IGF2-H19 locus in spermatozoa from infertile men
Specific epigenetic alterations of IGF2-H19 locus in spermatozoa from infertile men
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DOI：
10.1038/ejhg.2009.117
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发表时间：
2010-01-01
影响因子：
5.2
通讯作者：
Jammes, Helene
中科院分区：
文献类型：
--
作者：
Boissonnas, Celine Chalas;El Abdalaoui, Hafida;Jammes, Helene
DNA甲基化标记是印记的关键修饰，在原始生殖细胞中被擦除，在配子发生期间专门重新建立性别。异常的表观遗传程序被认为是影响男性生育能力的一种可能机制。我们用焦磷酸测序方法分析了精液正常男性、畸精症(T)和/或少弱精子症(OAT)患者精子中IGF2基因DMR0和DMR2以及H19 DMR的第3和第6个CTCF结合区的47个CpG的DNA甲基化状态。所有正常的精液样本在所有分析的CPGS中呈现出预期的高全球甲基化水平。在畸精症组中，19名患者中有11名在IGF2 DMR2或在IGF2 DMR2和H19 DMR的第6个CTCF的可变位点甲基化缺失。在OAT组中，22名患者中有16名患者出现了与精子密度密切相关的第6位CTCF甲基化的严重缺失。DMR0和第3 CTCF的甲基化状态不受精液病理状态的影响。本研究表明，H19DMR基因第6位CTCF位点的表观遗传扰动可能是人类精子发生数量缺陷的相关生物标志物。此外，我们定义了维持两组患者分类的甲基化阈值，未甲基化和甲基化患者。使用这一新的患者分类，观察到的精子固有印迹缺陷似乎不会显著损害辅助生殖技术的结果。《欧洲人类遗传学杂志》(2010年)第18期，第73-80期；DOI：10.1038/ejhg.2009.117；在线出版
DNA methylation marks, a key modification of imprinting, are erased in primordial germ cells and sex specifically re-established during gametogenesis. Abnormal epigenetic programming has been proposed as a possible mechanism compromising male fertility. We analysed by pyrosequencing the DNA methylation status of 47 CpGs located in differentially methylated regions (DMRs), the DMR0 and DMR2 of the IGF2 gene and in the 3rd and 6th CTCF-binding sites of the H19 DMR in human sperm from men with normal semen and patients with teratozoospermia (T) and/or oligo-astheno-teratozoospermia (OAT). All normal semen samples presented the expected high global methylation level for all CpGs analysed. In the teratozoospermia group, 11 of 19 patients presented a loss of methylation at variable CpG positions either in the IGF2 DMR2 or in both the IGF2 DMR2 and the 6th CTCF of the H19 DMR. In the OAT group, 16 of 22 patients presented a severe loss of methylation of the 6th CTCF, closely correlated with sperm concentration. The methylation state of DMR0 and of the 3rd CTCF was never affected by the pathological status of sperm samples. This study demonstrates that epigenetic perturbations of the 6th CTCF site of the H19 DMR might be a relevant biomarker for quantitative defects of spermatogenesis in humans. Moreover, we defined a methylation threshold sustaining the classification of patients in two groups, unmethylated and methylated. Using this new classification of patients, the observed intrinsic imprinting defects of spermatozoa appear not to impair significantly the outcome of assisted reproductive technologies. European Journal of Human Genetics (2010) 18, 73-80; doi:10.1038/ejhg.2009.117; published online 8 July 2009