Role of Genetics in Development
The mapping of human traits of the parents is the most important and primary area of the development of human genetics. This is significant especially in regard to abnormalities as well as conditions related to human genetical development such as Sickle cell disease, Huntington disease, Tay-Sachs disease, Down syndrome, Klinefelters syndrome, Turner syndrome and Cystic fibrosis (Miko, 2008). This paper will discuss the role of genetics in human development and analyze how the genes of the two parents influence the traits of an offspring. In particular, this paper will examine how such conditions can contribute to genetic or chromosomal abnormalities. The discussion in this paper will indicate the role of genetics in human development and the associated abnormalities in reference to Klinefelters syndrome and Turner syndrome.
The Role of Genetics on Development
History has provided evidence that human generations are born and molded from generation to another generation through genetics. From the beginning of life, biology sets the basis for human through the development of physical and mental aspects of life that shape their personality. This development is passed from the parents to children through genes passed at the embryo stage (Miko, 2008). When male reproductive cell and the female reproductive cell merge, fertilization process occurs to form the chromosomes for the new life. Out of these chromosomes, genes are developed comprising of DNA that maps the reproductive development of human beings.
All human cells except male and female reproductive cells are made of 46 chromosomes. To keep a perfect balance of the number of chromosomes in each cell when combining during fertilization, the male and female reproductive cells have 23 chromosomes each (Miko, 2008). Every human cell has certain genes that can develop from both or either of their parents but they will not have to be expressed. This aspect is called the phenotype which is the characteristic that is possible to be inherited by a person from the genes of the parent. For instance, a person may have a tall and a short parent which represents two opposite phenotypes, the one for tallness and the other for shortness.
Parents` influence to offspring Traits
The traits of the parents as referred to as phenotypes are therefore transferred to the offspring through the transfer of the DNA that contains the genes. The mother contributes the ovum which is the basis of reproduction while the father provides the sperm to fertilize the ovum (Berger, 2000). The sperm and ovum comprises of chromosomes which are long strands of deoxyribonucleic acid that bundled themselves together so as to replicate. Within the human cell nucleus are chromosomes that carry information that determines the traits of the offspring (Berger, 2000). For instance, the sex chromosome carry information that determines the gender of the offspring depending on the number of x and y chromosomes.
Genes are responsible for human characteristics such as blood type and the susceptibility of a person to diseases. Chromosomes are reproductive elements made up of several genes that guide the development of human traits. Chromosomal disorders occur when chromosomes are not well balanced in number or have abnormality in number or structure. According to Miko (2008) chromosomal disorders are syndromes that are characterized by malfunctions or malformations in the body system caused by abnormality in the number or structure of chromosome. This is because the foundation of genetics and inheritance of traits is based on the normal or the abnormal number and structures of genes and chromosomes (Miko, 2008).
Klinefelter`s syndrome and Turner Syndrome
Mostly occurring after fertilization, chromosomal abnormalities commonly take place if an error occurs during the processes of cell division after fertilization. Out of the 23 pairs of chromosomes, 22 of them normally determine the development of an individual regardless of the sex of the person (Klinefelter, 1986). The final pair that makes them 23 pairs normally has two sex chromosomes that dictate the sex of the offspring, whether a male or a female. The one for females contains two X chromosomes denoted as (XX) while that for males contains an X and a Y chromosome that is denoted as (XY).
In general, female chromosomes are denoted as 46, XX while that of the males is denoted as 46, XY. Klinefelter`s syndrome and Turner syndrome are the most in rare occasions due to the gender properties of the female chromosome (Klinefelter, 1986). Chromosomal disorders arise out of discrepancies in cytological description of respective sex chromosomes of the sex deviants. This makes people with Klinefelter`s syndrome to have a chromosomal denotation of XXY (Klinefelter, 1986).
It is evident that the main aspect of passing traits from parents to an offspring is controlled by genes and chromosomes. These are the carriers of information that dictate the trait or the phenotype to be passed on to the offspring. This information is based on the 46 chromosomes contained in every cell that merge during fertilization. Therefore, there is a chromosomal balance in terms of numbers and structure to be maintained. Any abnormality in the balance leads to a chromosomal disorder such as the Klinefelter`s syndrome and Turner syndrome.
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