线粒体三功能蛋白质缺陷是由深层内基缺失引起的,导致异常拼接
Thomas Cassini1, Sarah Silverstein2,3,4, Molly Behan5
1Division of Medical Genetics and Genomic Medicine, Department of Pediatrics Vanderbilt University Medical Center Nashville Tennessee USA.
JIMD reports
|December 26, 2024
概括
三功能蛋白质缺乏症 (TFP) 是一种罕见的脂肪酸氧化障碍. 基因分析揭示了HADHB的复合异构基因突变,解释了两个兄弟姐妹的严重TFP症状,包括FSGS和骨髓衰竭.
科学领域:
- 生物化学 生化学
- 遗传学 遗传学 是一个
- 儿科 儿科 儿科
背景情况:
- 三功能蛋白质缺乏症 (TFP) 是脂肪酸β-氧化的一种遗传性疾病.
- 严重的TFP表现为代谢,心脏和肝脏功能障碍.
- 这个案例突出了不常见的表现,如FSGS和骨髓衰竭.
研究的目的:
- 调查两位患有严重复杂临床表现的兄弟姐妹TFP的遗传基础.
- 在TFP相关基因中识别致病突变.
- 为了将基因型与观察到的表型相关联,包括FSGS和骨髓衰竭.
主要方法:
- 新生儿查和生物化学测试用于TFP诊断.
- 与TFP相关的基因 (HADHA,HADHB) 的桑格测序.
- 通过未诊断疾病网络进行全基因组和转录组测序.
- 对TFP中类似的临床表现的文献综述.
主要成果:
- 这两个兄弟姐妹都是两种不同的HADHB突变的复合异构.
- 一种父性遗传的无意义变异 (c.1059del) 和一种罕见的母性遗传的内基删除 (c.1390-515_1390-499del) 导致伪exon和过早终止codon.
- 鉴定的突变完全解释了TFP诊断和严重的表型,包括FSGS和骨髓衰竭,没有发现其他致病变体.
- 文献支持这些罕见发现与TFP的关联.
结论:
- 在HADHB中复合的异构基因突变导致严重的三功能蛋白质缺乏.
- 遗传发现为复杂的临床过程提供了完整的解释,包括FSGS和骨髓衰竭.
- 这项研究强调了先进基因测序在诊断具有异常表现的罕见代谢障碍方面的重要性.
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