Guella Ilaria, Rimoldi Valeria, Asselta Rosanna, Ardissino Diego, Francolini Maura, Martinelli Nicola, Girelli Domenico, Peyvandi Flora, Tubaro Marco, Merlini Pier Angelica, Mannucci Pier Mannuccio, Duga Stefano
Department of Biology and Genetics for Medical Sciences, University of Milan, Via Viotti 3/5, Milan, Italy.
Circ Cardiovasc Genet. 2009 Apr;2(2):165-72. doi: 10.1161/CIRCGENETICS.108.819326. Epub 2009 Feb 12.
Mutations in the MEF2A gene, coding for a member of the myocyte enhancer factor 2 family of transcription factors, have been reported in patients with coronary artery disease and myocardial infarction (MI). In particular, a 21-bp deletion and 3 missense mutations were demonstrated either to reduce MEF2A transcriptional activity or to impair its nuclear translocation. However, the association of MEF2A with coronary artery disease/MI was not confirmed in other studies. We analyzed the role of MEF2A in the pathogenesis of MI in 2008 Italian patients with premature MI and in 2008 controls.
Mutational screening of exon 8 (containing all so-far reported point mutations) disclosed 5 novel and 2 previously described missense mutations. Microsatellite genotyping and sequencing revealed the presence of the 21-bp deletion (located in exon 12) in 5 cases and in none of the controls. Functional studies on mutant proteins showed no alteration, neither in the transactivating properties (all mutants) nor in the nuclear localization (21-bp deletion). Furthermore, an association analysis performed using 3 microsatellites at the MEF2A locus showed no significant association with MI. These results were confirmed in a replication study performed on an independent Italian population with coronary artery disease.
All together, our data do not support MEF2A as a susceptibility gene for coronary artery disease/MI in the Italian population.
在冠状动脉疾病和心肌梗死(MI)患者中,已报道编码转录因子肌细胞增强因子2家族成员的MEF2A基因发生突变。特别是,已证实一个21碱基对的缺失和3个错义突变可降低MEF2A的转录活性或损害其核转位。然而,其他研究未证实MEF2A与冠状动脉疾病/MI之间的关联。我们分析了MEF2A在2008例意大利早发心肌梗死患者和2008例对照者心肌梗死发病机制中的作用。
对第8外显子(包含所有迄今报道的点突变)进行突变筛查,发现了5个新的和2个先前描述的错义突变。微卫星基因分型和测序显示,5例患者存在21碱基对的缺失(位于第12外显子),而对照组均未发现。对突变蛋白的功能研究表明,无论是反式激活特性(所有突变体)还是核定位(21碱基对缺失)均无改变。此外,使用MEF2A基因座的3个微卫星进行的关联分析显示与心肌梗死无显著关联。这些结果在对另一个独立的意大利冠状动脉疾病人群进行的重复研究中得到了证实。
总体而言,我们的数据不支持MEF2A作为意大利人群冠状动脉疾病/MI的易感基因。