Triple-X Syndrome (Trisomy X)
Introduction
Genetic disorders impact thousands of people every year. Triple-X Syndrome (Trisomy X) is a genetic disorder in females that have three X chromosomes instead of the regular two X chromosomes. Trisomy X was discovered by Patricia A. Jacobs back in 1959, and is named after the mutation of an extra third X chromosome. Trisomy X’s symptoms are diagnosed by taking certain tests. Trisomy X is not inherited by the parents. Treatment will vary depending on the level of symptoms you have and their degree of change to the body and mind. Trisomy X is only found in females.
Origin of Discovery Trisomy X has a very interesting origin of discovery. In a female there are two X chromosomes. In males they
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Some of those symptoms are tall stature, small head, vertical skin folds, speech and language learning disabilities, weak muscle tone, abnormal bending of the pinkie towards the ring finger, and wide spaced eyes. Lots of the symptoms are not noticed on the outside except through the way the child learns. If they learn at a normal rate then it is very unlikely they have this disease. Speech and language learning disabilities is a result of the damage to the motors in your brain from this disease. One very big inside symptom would be the absence of a kidney or even a deformed kidney. This kind of abnormality can cause urinary tract infections and other problems. Something like flat feet could be caused by the tall stature. Having to support all that extra body weight could cause your feet to have to adapt and that is where you would get your flat feet from. Also the body has to pump a lot more blood and so that can cause heart abnormalities. A lot of the symptoms of this disease are caused by the mutations or changes to the body to supply a bigger demand. By the bigger demand I mean the taller stature. The body has to compensate some how and these mutations to the body are just some of the ways the body compensates. All the other symptoms are just more of a problem then a way to compensate. Like the kidney abnormalities. That is a really bad symptom to get and that can cause a whole lot of pain and even more problems …show more content…
Trisomy X is not inherited from the parents so that can’t be a cause. To really get a grasp on what causes Trisomy X you have to know what it is first. So trisomy X is the addition of one extra X chromosome. X and Y chromosomes are the sex chromosomes that you get from your parents. The mother will always pass X chromosome, but the dad can pass either a X or Y chromosome. If the father passes an X chromosome then it will be a girl, and if the father passes a Y chromosome then it will be a girl. Now that we know what Trisomy X is we can get into what causes the disease. In a lot of cases where a female has Trisomy X the parents are usually older like the parent of the first case who were both in their forties. The reason this could be a factor is that age can cause the eggs to be deformed. Those deformities can cause a problem in cell division called nondisjunction. Since the cells don’t split right there could be a X chromosome accidentally put in the wrong cell which would cause all the other cells to have the extra X chromosome also. The disease is a genetic mutation which means that it does happen on purpose. It can happen to anyone even if the parents aren’t older. There is more of a risk for your child to develop this disease if you wait till later in life to
Twin studies have been used to distinguish between genetic and environmental factors for many disorders in the general population including ectodermal dysplasia, Ellis-van Creveld, and anencephaly. This review focuses on genetic disorders affecting monozygotic, dizygotic, and conjoined twins to gain a better understanding of them. Many studies focus on twins because they have a nearly identical genome, which eliminates environmental factors. In case studies, the concordance rates in monozygotic twins have supported that certain disorders were caused by genetics and not the environment. The discordant values in twins will also be evaluated briefly. Twinning studies have also shown linkages between specific disorders and the genes responsible for them. Knowing the location of these genes allows patients to be treated quickly and efficiently. This paper will discuss the possible causes of twinning and the various methods of identifying abnormalities in twins. These methods also allow preventive measures against the rise of birth defects during prenatal development. Epigenetics in twins is also viewed through the perspective of effects on them. Treatments for genetic disorders in twins are reviewed, ranging from the restoration of malformed teeth to the separation of conjoined twins. Support groups for twins in treatment, and their families are also briefly reviewed.
It is characterized by normal early growth and development followed by a slowing of development, the loss of purposeful use of the hands, slowed brain and head growth, problems with walking, seizures, and intellectual disability.
...can see if this condition runs in the family. A physical examination is a good way to tell is there is any type of muscle weakness or spinal curvature.
Turner’s syndrome is a genetic conditions that affects the female’s sex chromosome. In (http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001417/) Turner’s syndrome occurs when cells are missing all or part of an X chromosome. It’s common of the female patient to only have one X chromosome. Although, some individuals may have two X chromosomes but one is defective. It is thought that an estimated 1 out of 2000-2500 females suffer from this genetic condition worldwide but it’s usually females with this condition don’t survive their birth. Due to this abnormality, the genes that is defective “affect the growth and sexual development of the female” (http://learn.genetics.utah.edu/content/disorders/whataregd/turner/). However other disabilities and delays do occur even though these traits can vary case by case.
Turner’s affects the second X chromosome in a chromosome pair. This X is either incomplete or missing completely, which causes a decrease in fetal development and also a decrease in the development after birth. Since Turner’s affects the second X chromosome, this means that Turner’s only affects females. However, females of a certain race, nationality or those who live in a certain region of the world have the same risk of having Turner’s. One in every 2000 to 2500 baby girls are born with Turner’s, according to the National Health Service in the United Kingdom. Normally if a baby is conceived with an X chromosome missing, the body will naturally abort the baby, which is a miscarriage. Turner’s is usually the cause of almost 10% of miscarriages in the first trimester.
Jacob Syndrome is a rare condition where males contain an additional copy of the Y chromosome in their cells. According to the Genetic and Rare Diseases Information Center, (GARD, 2012), other names for Jacob Syndrome include: 47, XYY syndrome, XYY Karyotype, and YY syndrome. Statistics from Genetics Home Reference (2014) state that Jacob Syndrome appears in approximately 1 in 1,000 male newborns. In the United States, 5 to 10 male newborns have Jacob Syndrome.
The type of mutation that occurs in Down syndrome is aneuploidy that is the irregular number of chromosomes in a cell. The most common of the three is the trisomy 21 that occurs in about 90% of people with the disorder. In this factor the human is given three copies of the chromosome 21 instead of the common two copies. This occurs due to the complications of the cell division in the process of the egg or sperm. The next case is mosaic which happen when there are inequality of cells with three copies of chromosome 21 and others with the original two copies. Mosaic appears when there is an unexpected cell division after fertilization. The last and the rarest form is translocation and that happens while the chromosome 21 in cell division is broken off and attached to another chromosome. Since the disorder is unexpected there are numerous amounts of risk factors that are possible based on the severity of the person.
Some characteristics of DS are: deep folds at the corners of the eyes, hypotonia, short stature, flexible joints, small oral cavity and heart defects (Taylor, Richards, & Brady, 2005). Most individuals with DS have a moderate intellectual disability, although there is a range of disability, from severe to high functioning (IQ above 70). Since DS is a birth defect and not a disease, there are no treatment options. Improvement can be made through physicians, special education, physical therapy, speech therapy, occupational therapy, and psychol...
Sex-linked disorders only affect males and are passed down through female carriers. A boy inherits the disorder when he receives an X chromosome with a mutated dystrophin gene (the genetic cause) from his mother. The dystrophin gene is the largest gene found in nature and was identified through a positional cloning approach. It's a highly complex gene, a large rod-like cytoskeletal protein which is found at the inner surface of muscle fibers. (www.ncbi.nlm.nih.gov)
Obvious signs include crooked spine while bending over, fatigue, shortness of breath, uneven hemline on shirts, and an asymmetrical waistline. Less obvious signs must be detected by health professionals through early screening, or diagnosed by your physician during a comprehensive physical exam.
A Karyotype is when you cut out individual chromosomes from a picture and rearrange them. There are matching pairs of chromosomes these are called homologous pairs. Each pair is given a number. One of each pair came from the mother and one of each pair came from the father. The pairs can be distinguished as each pair has a distinctive banding pattern when stained. There are two sex chromosomes and the rest are called autosomes. In most karyotype the sex cells are kept to one side so that the sex can be seen easily. In females they have two X chromosomes and in the males they have an X and a Y chromosome. The Y chromosome has a portion missing and is therefore smaller then the X chromosome.
He published a comprehensive medical description of the syndrome. It was not until 1959, that it became clear the syndrome was due to lack of sex chromosome material. Turner's Syndrome is a rare chromosomal disorder that affects one in approximately 2,500 females. Females normally have two X-chromosomes. However, in those with Turner's Syndrome, one X chromosome is absent or is damaged.
Klinefelter syndrome is a chromosomal abnormality that leads to alterations in the male phenotype. These alterations appear in both the physical and cognitive development ("Klinefelter syndrome - Genetics Home Reference", n.d.). Males affected by this disorder carry an extra X chromosome, which results in androgen deficiency, hypogonadism, and infertility (Smyth, 1998). Instead of being inherited, Klinefelter syndrome is due to spontaneous events during the formation of the parental germ cells. These events lead to an extra X chromosome in the cells of the offspring ("Klinefelter syndrome - Genetics Home Reference", n.d.).
XYY Syndrome is a rare genetic disorder which affects males due to an extra Y chromosome. Healthy males have 46 chromosomes including one X and one Y chromosome. Men with XYY syndrome have 47 chromosomes, two of which are Y chromosomes. It is not known why the extra Y chromosome occurs. The disorder is present at birth and is estimated to occur in one out of every one thousand live births.