First estimation of the scale of canonical 5’ splice site GT>GC mutations generating wild-type transcripts and their medical genetic implications
First estimation of the scale of canonical 5’ splice site GT>GC mutations generating wild-type transcripts and their medical genetic implications
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DOI：
10.1101/479493
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发表时间：
2018-11
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影响因子：
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通讯作者：
Jin‐Huan Lin;Xin-Ying Tang;A. Boulling;Wen‐Bin Zou;E. Masson;Y. Fichou;L. Raud;M. Tertre;
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文献类型：
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作者：
Jin‐Huan Lin;Xin-Ying Tang;A. Boulling;Wen‐Bin Zou;E. Masson;Y. Fichou;L. Raud;M. Tertre;
人们早就知道，规范5 ‘剪接位点（5 ’ ss） GT>GC突变可能与正常剪接兼容。然而，到目前为止，在这种突变的频率和突变等位基因产生的野生型转录本水平的背景下，典型的5'SS GT b> GC突变产生野生型转录本的真实规模仍然未知。本文结合对45个致病5ss GT>GC突变（来自42个基因）的荟萃分析数据和103个5ss GT>GC突变（来自30个基因）的基于细胞培养的全长基因剪接试验，我们估计，由于GC替代了GT，约15-18%的典型GT 5sss能够产生1 - 84%的正常转录本。我们进一步证明，用GC取代GT产生正常转录本的典型5sss与U1 snRNA 5 '端的互补性比那些用GC取代GT没有产生正常转录本的位点强。我们还观察到野生型转录本的产生与比预期温和的临床表型之间存在相关性，但发现没有任何可用的剪接预测工具能够准确预测5ss GT>GC突变的功能影响。我们的研究结果表明，5ss GT b> GC突变可能并不一定会导致人类疾病，但也应该有助于提高我们对哺乳动物中t2型内含子GT>GC亚型转换的进化过程的理解。
It has long been known that canonical 5’ splice site (5’SS) GT>GC mutations may be compatible with normal splicing. However, to date, the true scale of canonical 5’SS GT>GC mutations generating wild-type transcripts, both in the context of the frequency of such mutations and the level of wild-type transcripts generated from the mutation alleles, remain unknown. Herein, combining data derived from a meta-analysis of 45 informative disease-causing 5’SS GT>GC mutations (from 42 genes) and a cell culture-based full-length gene splicing assay of 103 5’SS GT>GC mutations (from 30 genes), we estimate that ∼15-18% of the canonical GT 5’SSs are capable of generating between 1 and 84% normal transcripts as a consequence of the substitution of GT by GC. We further demonstrate that the canonical 5’SSs whose substitutions of GT by GC generated normal transcripts show stronger complementarity to the 5’ end of U1 snRNA than those sites whose substitutions of GT by GC did not lead to the generation of normal transcripts. We also observed a correlation between the generation of wild-type transcripts and a milder than expected clinical phenotype but found that none of the available splicing prediction tools were able to accurately predict the functional impact of 5’SS GT>GC mutations. Our findings imply that 5’SS GT>GC mutations may not invariably cause human disease but should also help to improve our understanding of the evolutionary processes that accompanied GT>GC subtype switching of U2-type introns in mammals.