罕见的自身免疫位子编码区域变异对遗传性缺失的影响微不足道
Karen A Hunt1, Vanisha Mistry, Nicholas A Bockett
1Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London E1 2AT, UK.
Nature
|May 24, 2013
概括
罕见的编码区域变异在常见的自身免疫性疾病易感性中起到最小的作用. 这项研究表明,在这些疾病中缺失遗传性可能是由于许多常见变异,而不是罕见的变异.
科学领域:
- 遗传学 是一个遗传学.
- 免疫学 免疫学 免疫学
- 人口健康 人口健康
背景情况:
- 全基因组关联研究 (GWAS) 已经确定了与自身免疫性疾病相关的众多常见变异,但遗传性的很大一部分仍然无法解释.
- 罕见的变异被假设为这种缺失的遗传性做出贡献,促使人们对它们的作用进行调查.
研究的目的:
- 调查罕见编码区域变异对常见自身免疫性疾病易感性的作用.
- 为了测试罕见变异的合成基因组广泛关联假设.
主要方法:
- 同时基于安普利康序列的变体发现和基因定型.
- 对25个已知的自身免疫性疾病风险基因中的编码外基因的分析.
- 这是一项针对41,911名英国居民 (24,892例病例和17019例对照病例) 的大型队列研究.
主要成果:
- 在已知的自身免疫性疾病位点的罕见编码区域变异对疾病易感性有微不足道的影响.
- 这些发现不支持罕见变异合成全基因组关联假设.
- 这项研究表明,常见的弱效变异可能解释了遗传能力的缺失.
结论:
- 在常见的自身免疫性疾病中缺失的遗传性不太可能由罕见的编码区域变异来解释.
- 未来的研究应该专注于许多常见的变体与小效果大小对自身免疫性疾病风险的贡献.
相关概念视频
Principles of Pharmacogenetics: Types of Genetic Variants
The human genome is over 99.9% identical between individuals, yet genetic differences exist at millions of bases. The human genome contains approximately 3 million variant positions per individual, many of which are heterozygous, contributing to genetic diversity and individual traits. Genetic variations include single-nucleotide polymorphisms (SNPs), insertions, deletions, and copy number variations (CNVs).SNPs, the most common variation, involve single-base changes in DNA. These can be...
Genome-wide Association Studies-GWAS
Genome-wide association studies or GWAS are used to identify whether common SNPs are associated with certain diseases. Suppose specific SNPs are more frequently observed in individuals with a particular disease than those without the disease. In that case, those SNPs are said to be associated with the disease. Chi-square analysis is performed to check the probability of the allele likely to be associated with the disease.
GWAS does not require the identification of the target gene involved in...
GWAS does not require the identification of the target gene involved in...
Comparing Copy Number Variations and SNPs
Sequencing of the human genome has opened up several best-kept secrets of the genome. Scientists have identified thousands of genome variations that exist within a population. These variations can be a single nucleotide or a larger chromosomal variation.
Copy number variations or CNVs are the structural variations that cover more than 1kb of DNA sequence. The single nucleotide polymorphism (SNP), on the other hand, is a single nucleotide change or a point mutation that is found in more than 1%...
Copy number variations or CNVs are the structural variations that cover more than 1kb of DNA sequence. The single nucleotide polymorphism (SNP), on the other hand, is a single nucleotide change or a point mutation that is found in more than 1%...
Single Nucleotide Polymorphisms-SNPs
A single nucleotide polymorphism or SNP is a single nucleotide variation at a specific genomic position in a large population. It is the most prevalent type of sequence variation found in the human genome. Point mutations that occur in more than 1% of the population qualify as SNPs. These are present once every 1000 nucleotides on an average in the human genome. Replacement of a purine with another purine (A/G) or a pyrimidine with another pyrimidine (C/T) is known as a transition. In contrast,...
Incomplete Dominance
Gregor Mendel's work (1822 - 1884) was primarily focused on pea plants. Through his initial experiments, he determined that every gene in a diploid cell has two variants called alleles inherited from each parent. He suggested that amongst these two alleles, one allele is dominant in character and the other recessive. The combination of alleles determines the phenotype of a gene in an organism.
Pleiotropy
Pleiotropy is the phenomenon in which a single gene impacts multiple, seemingly unrelated phenotypic traits. For example, defects in the SOX10 gene cause Waardenburg Syndrome Type 4, or WS4, which can cause defects in pigmentation, hearing impairments, and an absence of intestinal contractions necessary for elimination. This diversity of phenotypes results from the expression pattern of SOX10 in early embryonic and fetal development. SOX10 is found in neural crest cells that form melanocytes,...

