Disorders Involving the Sex Chromosomes - Term Paper Example

Disorders involving the sex chromosomes Sex chromosomes are those that determine the gender of individuals to be either male or female. The sex chromosomes face several disorders that arise from the deletion or addition of the sex chromosomes; X and Y. chromosomes are made up of long strands of the genetic material deoxyribonucleic acid, DNA that contains several genes that are responsible for the various traits in human beings (Gardner, Sutherland and Shaffer 123). The chromosomes are numbered such that they are given the numerical figures 1…..22 and the 23rd is the one that determines the individual sex. In total there are 23 chromosomes in human beings, the 23d being the sex chromosome with x and y as the determinants. In the normal female, the chromosome number 23 will read xx while that of the male will be reading XY (Pinsky, Erickson and Schimke 234). The alteration of the normal reading leads to what is called chromosomal disorders. The chromosomal disorders leads to the addition or deletion of either X or Y-chromosomes. Several disorders have been identified as disorders in the sex chromosomes and demonstrate distinct characteristics as manifested phenotypically (Goldberg 157). It must be noted that there are significant difference between the disorders that arise from the autosomal chromosomes (1…22) and those of the sex chromosomes (Passarge 98). The chromosomes that determine sex in man is coded as XY while that of females is XX, the alteration of the arrangements may lead to any of the following conditions. Turner Syndrome It is coded as XO; it is referred to as monosomy X given that the complement Y-chromosomes is missing. The fact that the syndrome results into just one X chromosome without the Y chromosome, such individuals are always females (Milunsky and Milunsky 245). The incidence of the syndrome is quite uncommon and can only be found one in every five thousand people. One of the most significant effects of the condition is sterility (Milunsky and Milunsky 256). Klinefelter Syndrome This is also a rare syndrome as for every 1000 there is only one person with the condition. Unlike Turners syndrome that involves deletion of the Y chromosome, it involves the addition of the X chromosomes (Goldberg 165). The syndrome can appear in two forms XXY or XXXY. Most of the individuals affected by this kind of disorder are males due to the presence of the Y-chromosomes. The presence of the compounded X chromosomes makes the individuals with the condition to posses female like qualities. The individuals are sterile and in the cases of the XXXY type retardation may results (Goldberg 184). Jacobs Syndrome In the Jacobs syndrome the individuals have the sex chromosomes coded as XYY, there is an additional Y chromosome and the individuals are always males or abnormally manifest male characteristics (Passarge 112). These individuals are supper human beings as they are very tall and in many cases may suffer from acne. Research also indicates that most of these people are criminals as they show abnormally high-level aggression and most of the inmates are of these conditions. The frequency of this syndrome is 1 in every 2000 (Passarge 119). Triple-X Most of the individuals in this category are females as the syndrome involves the addition of the X chromosome and the various codes are as follows XXX, XXXX, and XXXXX (Pinsky, Erickson and Schimke 253). Due to the extra X chromosomes, the casualties assume abnormal female characteristics and the associated problems such as those of infertility as well as retarded mental acuity. The occurrence of this syndrome is in the frequency of 1 in every 700 individuals (Pinsky, Erickson and Schimke 257). With the realization of the fact that sex chromosomes have defects that can lead to the changes in the phenotypic characteristics of individuals has sparked a series of researches in the field of genetics. One of the current research researches that is currently on going is the identification of the component of that is essential for life in the X chromosomes. He research has become necessary since in all the alteration of the chromosomal composition there is none of them that result into such alteration as YO (Milunsky and Milunsky 298). At least, there has to be the X chromosomes in the changes, the occurrence of the X chromosome has been eluded to contain certain essential elements necessary for life, and those supposed elements have not been identified and documented. Research is thus going on to establish the reasons as to why there has to be the X chromosome in any of the chromosomal disorder. In other areas are also researches on the nexus between the breast cancer in men and the klinefelters syndrome. The syndrome has been linked in many hypotheses to aggravate the condition of men in developing the cancer of the breast. It has thus become an area of interest to identify how the condition of the syndrome kindles the abnormal proliferation of the cells. Several individuals with the syndrome have been put for studies in which they are followed for the development of the disorder to confirm that it is probable that the hypotheses in deed are true. In developing the research for the new concerns in the sex chromosomes, researchers hinge most of their interest in the already documented facts about the disorders. In most if the disorders, there are considerable facts known about them. For instance in the klinefelter syndrome, it is known that there is an additional X chromosome, it is also known that the syndrome results into the additional chromosome making the total chromosomes to be 47 i.e. 47 XXY. It is also known that the different syndromes demonstrate different characteristics in human beings. In some cases, the occurrence of the various syndromes pre disposes an individual to develop some other medical conditions like diabetes, thyroid problems, and development of ulcers. Most importantly is the identification of the type of chromosome that is affected in the various disorders, this has been important in knowing what kind of condition occurs in which gender. The incidence of the syndromes is also known confirming that they are those that occur rarely according to the statistics taken about the various forms of the syndromes. For example in the Jacob syndrome, the incidence is 1 out of every 2000 individuals (Passarge 161). The researches currently on going are geared towards establishing new facts that are not known now. Some of the facts that are not within our knowledge now include reason as to why there is no any disorder that has missing X chromosome resulting into the YO form. It is probable that the X chromosome is of great value to ensure there is life and therefore has to be present in either form of the chromosomal alterations. What is not known is thus the absence of the YO form of chromosomal disorder. Works cited Gardner, R. J. M., Grant R Sutherland and Lisa G Shaffer. Chromosome Abnormalities and Genetic Counseling. New York: Oxford University Press, 2011. Print. Goldberg, Deborah T. Barron's AP Biology. New York: Barron's Educational Series, 2010. Print. Milunsky, Aubrey and Jeff Milunsky. Genetic Disorders and the Fetus: Diagnosis, Prevention and Treatment. John Wiley & Sons, 2011. Print. Passarge, Eberhard. Color atlas of genetics. Thieme, 2007. Print. Pinsky, Leonard, Robert P Erickson and R Neil Schimke. Genetic disorders of human sexual development. New York: Oxford University Press, 1999. Print. Read More