在MITF中,一个新的2.3kb结构变体解释了纯血统家族中的新型喷白色表型
R R Bellone1,2, J Tanaka1, E Esdaile1
1Veterinary Genetics Laboratory, School of Veterinary Medicine, UC Davis, Davis, California, USA.
Animal genetics
|September 12, 2023
概括
在纯种马身上发现了一种新的微症相关转录因子 (MITF) 基因缺失,称为SW8,导致广泛的白色外套模式和聋. 这一发现突出了第四个新的MITF变异,与马匹白斑有关.
科学领域:
- 遗传学和基因组学 遗传学和基因组学
- 动物科学动物科学
- 分子生物学分子生物学
背景情况:
- 喷的白马表现出广泛的白色图案和潜在的聋.
- 之前的研究已经确定了七种与微相关的转录因子 (MITF) 和两种与这种表型相关的Paired Box 3 (PAX3) 变异.
- 喷白色图案的新发病例的遗传基础在很大程度上仍然无法解释.
研究的目的:
- 为了确定白色外套图案的遗传原因在纯种马,没有它的父母的特征的历史.
- 为了描述潜在的新突变,负责喷白色表型.
主要方法:
- 采用全基因组测序来识别受影响马的遗传变异.
- 候选基因分析的重点是MITF和SOX10.
- 桑格测序,亲属测试和后代的基因定型被用于确认突变的起源和遗传.
主要成果:
- 在名为SW8的MITF基因 (NC_009159.3:g.21555811_21558139delinsAAAT) 中出现了新的2.3 kb删除,被确定为可能的因果变异.
- 这种删除包括对MITF的螺旋环-螺旋环-螺旋环DNA结合域至关重要的第9个外显子.
- SW8是由一个几乎全是白色的聋子小继承的,这也是主导白色变体 (W20/W22) 的复合异构体.
结论:
- SW8代表了第四个报告的 de novo MITF 变种,导致马匹的白色图案.
- 这项研究证实了MITF中母源的de novo突变导致喷白色表型和相关的聋.
- 需要进一步的研究来探索MITF变体与马的聋之间的关系,特别是与其他与黑色素细胞相关的基因结合.
相关概念视频
Animal Mitochondrial Genetics
7.6K
Among all the organelles in an animal cell, only mitochondria have their own independent genomes. Animal mitochondrial DNA is a double-stranded, closed-circular molecule with around 20,000 base pairs. Mitochondrial DNA is unique in that one of its two strands, the heavy, or H, -strand is guanine rich, whereas the complementary strand is cytosine rich and called the light, or L, -strand. Compared to nuclear DNA, mitochondrial DNA has a very low percentage of non-coding regions and is marked by...
7.6K
Incomplete Dominance
22.7K
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.
22.7K
Epistasis
46.9K
In addition to multiple alleles at the same locus influencing traits, numerous genes or alleles at different locations may interact and influence phenotypes in a phenomenon called epistasis. For example, rabbit fur can be black or brown depending on whether the animal is homozygous dominant or heterozygous at a TYRP1 locus. However, if the rabbit is also homozygous recessive at a locus on the tyrosinase gene (TYR), it will have an unshaded coat that appears white, regardless of its TYRP1...
46.9K
Genetic Variation
321
Genetic variation is the diversity in DNA sequences found among individuals of the same species. This diversity is crucial for a species' survival because it helps organisms adapt to environmental changes. Genetic variation begins with fertilization, where an egg and sperm cell merge. Each of these cells carries 23 chromosomes, up to 46 in the fertilized egg. Chromosomes are long DNA strands that contain genes, the basic units of heredity.
Genes exist in different versions called alleles,...
Genes exist in different versions called alleles,...
321
Point and Frameshift Mutations
33
Point mutations are genetic alterations involving the change of a single nucleotide base pair in DNA. Depending on how the alteration affects protein synthesis, they can lead to various consequences.Point mutations fall into the following types:Silent mutations occur when a nucleotide change does not alter the amino acid sequence due to the redundancy of the genetic code. For instance, changing ACC to ACA still encodes threonine, leaving the protein function unaffected. This occurs because...
33
Single Nucleotide Polymorphisms-SNPs
15.2K
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,...
15.2K


