基因突变,痴呆 z-bo 2020-10-20 334

　　In the latest research paper published in the international journal Nature, researchers at Johns Hopkins University found that common genetic mutations associate brain damage with amyotrophic lateral sclerosis (ALS) and frontotemporal lobe. Researchers in dementia (frontotemporaldementia, FTD) have shown that changes in the C9orf72 gene on human chromosome 9 promote RNA molecules and block important pathways for protein transport, causing the brain. A normal function that causes molecular "traffic congestion" outside the human core, which in turn affects the brain. According to researcher Dr. Jeffreyothstein, this common genetic mutation is associated with 40% of hereditary ALS cases, 25% of hereditary FTD is directly related, and about 10% of non-genetic diseases. Point out relevant. The main feature of ALS and FTD is that the nerve cells in the patient's brain will continue to degenerate over time. Taking FTD as an example, injury may cause problems in the patient’s conversation, language understanding, and emotional processing. In ALS patients, degenerated nerve cells affect spinal cord and brain function, and the patient will eventually lose the ability to control muscles.

　　This gene mutation called C9orf72 does not change the composition of DNA, but repeats the 6-DNA nucleotide chain thousands of times. When DNA mutations occur, they affect the production of long chains in cells. NA replication; In 2013, researchers identified more than 400 special intracellular proteins, and repeated RNA strands can directly act on these proteins. In this study, the researchers focused on a protein called RanGAP. , Protein can mediate the action of mutant RNA in cells. In healthy cells, the protein RanGAP can transport molecules through the nuclear pore complex that connects the cytoplasm. This study uses human brain cells with C9orf72 mutations associated with ALS. Stateful, RanGAP-dependent nuclear transporters will not flow through the nucleus pores. In another experiment, the researchers used Drosophila and human stem cells to conduct research and added antisense oligonucleotides to prevent the interaction of antisense oligonucleotides with RanGAP and interfere with the nuclear pore complex. I found my body. The body starts to work again. At present, researchers do not yet understand the specific mechanism of gene C9orf72 mutation and cell death at various stages of the brain, but later further studies were carried out to clarify why C9orf72 mutation causes ALS and FTD.