What are genes and why are they important?
Genes
are made up of DNA, which determines what an organism looks like, how it
survives, and how it behaves in its environment. All living organisms have
genes, which can also affect a person's health throughout their life
The
genomes of living organisms differ in the number of genes they contain. The
human genome contains about 30,000 genes
Human
genomes are 99.9% identical in nucleotide sequence, with only minor genetic
differences leading to visible physical differences. These differences may be
inherited or the result of the interaction between a person's genes and the
environment. It can also explain why some people suffer from certain diseases
and others do not
A
geneticist is a person who studies genes and how to target them to improve
aspects of life. Genetic engineering can provide a range of benefits to people,
including the prevention of diseases in humans
What is the definition of gene?
The
gene, in short, is the structural and functional unit of genetic material that
is transmitted from parents to children, from generation to generation, and so
on, until Allah inherits the earth and those on it.
The
gene occupies a specific location on the chromosome known as the locus that
does not change within a single species. In metaphase, the chromosome consists
of two arms, P and Q, separated by the centromere. The centromere appears
during division as a shortened central region when the two chromatids appear in
the shape of an X.
The
gene that determines a characteristic, such as flower color or eye color in
humans, has two or more forms. the flower may be red, green, or yellow. the
eye color may be black, blue, or hazel... or height and shortness. The
different forms of a gene are known as alleles
When the chromosome is stained, it appears as areas of varying pigmentation, some of which are light and others are dark. The dark areas are known as heterochromatin (heterochromatin) and the light areas are known as euchromatin (euchromatin). Euchromatin is the place in the chromosome where genes are active.
Genes
consist of a long chain of four different nucleotides. They are the basic
building blocks of DNA. The four types of bases found in nucleotides are:
adenine, cytosine, guanine, and thymine. Genes consist of two strands wrapped
around each other. They are connected to each other through links between the
rules. Adenine pairs with thymine. Cytosine pairs with guanine. The sequence of
these bases determines the instructions in the DNA strand. For example, the
sequence ATCGTT might direct for blue eyes, while ATCGCT might direct for brown
eyes.
Human
chromosomes range in size from about 50 million to 300 million base pairs. The
entire human genome contains about 3 billion bases and about 20,000 genes on 23
pairs of chromosomes in humans.
What are genes functions?
A
gene is composed of a sequence of nucleotides or a specific DNA structure. By
gene expression, we mean the process through which the information in the gene
is transformed into protein or RNA.
The
gene is composed of coding sequences (exon) and non-coding sequences (intron).
During the processing of the messenger RNA, the introns are removed. The
intron-free messenger RNA is the RNA that is used as a template for making
proteins.
A
gene generally consists of: exons, start codons, termination codons, and
regulatory control elements.
Parts
of some exons or some exons may contain sequences that are not translated into
amino acids, such as the untranslated part of the first exon and the third exon
in the above figure.
The
average number of exons ranges from 7 to 10, spread across 10 to 16 kilobases
of DNA.
Different
forms of messenger RNA may arise from the same gene, giving different types of
proteins with different functions, and this is known as alternative
transcription. About 60% of human genes have this type of copy. One of the
advantages of this type of copying is that a limited number of genes control
many traits.
For more information about the gene, watch the attached video.
How do genes affect health?
Genes
influence hundreds of internal and external factors, such as whether a person
will have a certain eye color or what diseases he may develop.
Changes
in genes can also lead to the formation of incorrect proteins that cannot
perform their functions. These are called genetic mutations and may lead to
hereditary disorders
Some
diseases, such as sickle cell anemia and Huntington's disease, are caused by
genetic mutations. Because genes are passed from parents to children, some
diseases tend to run in families
Genetic
mutations can also occur due to exposure to toxins found in the environment,
such as cigarette smoke.
References
https://www.ncbi.nlm.nih.gov/books/NBK26821/
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