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Homozygous and Heterozygous

Heterozygous and homozygous are words used in biology and genetics to describe whether a living thing has two identical copies of the same gene or two distinct copies.

Homozygous means that an organism has the same two copies of a gene, whereas heterozygous means that an organism has different copies of a gene for a certain feature. These creatures are referred to as homozygote and heterozygote in plant and animal reproduction.

Source of homozygous and heterozygous

Both homozygous and heterozygous derive from the root zygo-, which means “yoke” or “yoked,” as in “paired together.” adjectives are formed using the suffix -ous. The distinction begins with the greek prefix hetero-, which means “different,” and homo-, which means “same.” This is an excellent method to remember the distinction and what it implies in practice.

Homozygous

Homozygous is a genetic situation in which a person receives the same alleles of both parents for a particular gene.

Heterozygous

Heterozygous inheritance is a genetic situation in which a person receives two distinct alleles of a gene from each parent.

What is the distinction between homozygous and heterozygous genetic status?

Organisms that are homozygous have two copies of a certain allele. An allele is a variant of a gene, akin to a “taste.” Each gene in humans and other diploid creatures is duplicated twice. (diploid creatures, by definition, have two copies of each chromosome.)

It is frequently beneficial to break down vocabulary in order to better retain meanings. Homo- denotes identical, but hetero- indicates dissimilar. -zygous denotes the possession of a certain kind of zygote (a specific combination of genetic material).

The term “homozygous” refers to the possession of two alleles that are exactly the same.

Heterozygous refers to the presence of two distinct alleles.

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Examples of homozygous genotypes

Eye color

  • The predominant genetic characteristic for eye colour is brown, indicated by the BB genotype.

  • If the genotype is homozygous, the eye colour genes on both chromosomes should be similar.

Freckles

  • The MC1R gene controls the generation of freckles, which are small patches on the skin generated by melanin pigment.

  • People with freckles have a homozygous-dominant genotype, which means they express the dominant allele more than others.

Examples of heterozygous genotypes

Sickle-cell anemia

  • The dominant phenotype is manifested in those with heterozygous genotype, avoiding sickle-cell anaemia.

  • In sickle-cell anaemia, the red blood cells become sickle-shaped, making them tiny and unable to transport enough oxygen.

  • As a result, persons with sickle-cell anaemia benefit from having a heterozygous genotype.

Curly hair

  • Only persons with homozygous-recessive alleles have straight hair, because this gene is important for producing a protein that causes hair to curl.

  • This condition is also known as incomplete dominance, when the phenotype is displayed between the dominant and recessive ones.

  • Curly hair strands are present in persons with heterozygous status in total dominance

How can you determine if you are homozygous or heterozygous for a gene?

When both alleles of a gene are identical, the individual is said to be homozygous for that specific gene. Example: This might imply that you have two alleles of the gene that causes brown eyes. In certain cases, some alleles have a dominant influence, whereas in other cases, it is the reverse. You have a heterozygous genotype if the two variants are both heterozygous for the gene in question. For example, being heterozygous for hair colour implies that you have one allele that causes red hair and another that causes brown hair, and so on. The relationship between the two alleles determines which characteristics are manifested in the individual.

Conclusion

Both of these phrases are commonly followed by the term for and the quality that distinguishes them from the others. To be homozygous for a trait, a person must have identical pairings of the genes (also known as alleles) that influence the characteristic’s development in both parents. Heterozygous for a trait indicates that you have a large number of alleles for that characteristic.

 
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Humans are heterozygous or homozygous for certain genes.

Ans. Humans have two chromosome sets. In order to distinguish between allele pairs, the terms homozygous and heteroz...Read full

Persons that are homozygous for a certain gene are referred to as homozygous individuals

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Is homozygous recessive or dominant?

Ans. In genetics, a homozygous dominant genotype is an organism that possesses two dominant alleles for a certain fe...Read full

How do you determine the frequency of alleles?

Ans. The term “allele frequency” refers to the frequency with which an allele occurs in a population. It...Read full

How do you determine the frequency of homozygous recessive alleles?

Ans. 1 = p2 + 2pq + q2. P and q each denote the allele frequency of a c...Read full