在人类del22q11.2综合征中TBX1的作用
Hisato Yagi1, Yoshiyuki Furutani, Hiromichi Hamada
1Division of Genomic Medicine, Institute of Advanced Biomedical Engineering and Science, Graduate School of Medicine, Tokyo Women's Medical University, Tokyo, Japan.
Lancet (London, England)
|October 31, 2003
概括
染色体22q11.2的删除会导致一个常见的微删除综合征. TBX1基因突变被确定为这种综合征的重要遗传原因,即使没有完全删除.
科学领域:
- 遗传学 是一个遗传学.
- 分子生物学分子生物学
- 人类疾病 人类疾病
背景情况:
- 22q11.2删除综合征是一种频繁的微删除综合征,影响4000-5000个活产中的1个.
- 它的特征是心脏缺陷,T细胞缺陷,口腔裂,面部异常和低血症,它涉及染色体22q11.2上的3Mb删除,具有众多映射基因.
- 这些基因在导致综合征的确切作用尚不清楚.
研究的目的:
- 为了研究22q11.2删除综合征的遗传基础.
- 确定TBX1基因的突变是否有助于该综合征的表型,特别是在没有典型删除的个体中.
主要方法:
- 在235名被诊断为del22q11.2综合征的患者身上,在22q11.2上使用10个探针进行了光现场杂交 (FISH) 分析.
- 对TBX1编码序列的基因分析在13名表现出22q11.2综合征表型但缺乏可检测的缺失的患者中进行.
主要成果:
- 在96% (225/235) 的患者中,在22q11.2确定了1.5-3Mb的删除.
- 在两名没有22q11.2删除的无关患者中发现了三种TBX1突变,这些患者呈现出面部/心肌面部综合征或迪乔治综合征的圆柱形异常.
- 这些突变还在三名患有圆柱形异常面部/心肌面部综合征的家庭患者中发现,在555名健康对照中 (p<0.0001) 缺席.
结论:
- TBX1突变涉及导致与22q11.2删除综合征相关的五种主要表型.
- 该研究得出结论,TBX1是22q11.2删除综合征的关键遗传决定因素.
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