Thekey differencebetween dominant and recessive alleles is thatdominant alleles are the alleles that give thephenotype, masking over the other phenotype, while recessive alleles are the alleles that are suppressed by the dominant allele.
Usually, a chromosome contains a number ofgenes, and they exist in specific places. If genes exist in the same location in thehomologous chromosomes, they are said to have the same locus. Since they are present in the same loci of the maternal and paternal chromosome, these genes have the sametrait. They are the alternative forms of a gene; we call these alleles. Alleles can be dominant or recessive. A dominant allele always gives the phenotype it codes while the recessive allele gives the phenotype only when it is present in the homozygous state. Actually, dominance and recessivity are the phenotypic correlation of two alleles.
内容
1.Overview and Key Difference
2.What are Dominant Alleles
3.What are Recessive Alleles
4.Similarities Between Dominant and Recessive Alleles
5.并排比较 - 表格形式的主要与隐性等位基因
6.概括
What are Dominant Alleles?
The dominant allele is the strongest allele among the two forms of a gene present in the same loci of the maternal and paternal chromosome. The trait of the dominant allele is always expressed when the gene occurs in both homozygous dominant and heterozygous states.
例如,如果我们将主要等位基因视为(a)和隐性等位基因为(a),那么在纯合子的情况下,我们可以将两个等位基因写为AA。就杂合子而言,我们可以将其写为AA。在这两种情况下,主要的等位基因都可以在隐性等位基因上表达其表型。因此,主要等位基因掩盖了隐性等位基因的表型。
What are Recessive Alleles?
The recessive allele is the weaker allele among the two alleles of a gene. It is expressed only in the case of homozygous. In the case of heterozygous, the dominant allele masks the phenotype of the recessive allele. For instance, if we consider the dominant allele as (A) and recessive allele as (a), the recessive allele can express its phenotype only in the case of ‘aa’. Thus, it is not expressed in its Aa state due to the effect of the dominant allele.
What are the Similarities Between Dominant and Recessive Alleles?
- Dominant and recessive alleles are two possible forms of a gene.
- Both encode for a trait.
- Also, both are at the same locus.
- Furthermore, when they are present in the homozygous state, they give their respective phenotypes.
What is the Difference Between Dominant and Recessive Alleles?
Dominant allele is the stronger allele from the two alleles, and the weaker one is the recessive allele. A dominant allele can express its phenotype in both its heterozygous and homozygous states, but a recessive allele can express its phenotype only in its homozygous state or when the dominant allele is absent. So, this is the key difference between dominant and recessive alleles.
Below infogrphic shows the difference between dominant and recessive alleles, comparatively.
概括– Dominant vs Recessive Alleles
Each parent contributes one allele to each gene. Therefore, each gene generally has two alleles. Moreover, there are two types of alleles as dominant allele and recessive allele. The dominant allele is the stronger allele that determines the phenotype. It can mask the phenotype of the weaker allele, which is the recessive allele. The recessive allele can express its phenotype only when it is present in the homozygous recessive state. But dominant allele can express its phenotype in both homozygous dominant and heterozygous states. Thus, this is the summary of the difference between dominant and recessive alleles.
Reference:
1. “Dominance (Genetics).” Wikipedia, Wikimedia Foundation, 22 Apr. 2019,Available here.
Image Courtesy:
1. “Genotype” ByGETaiwan NTU(CC BY-SA 2.0)viaFlickr
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