Aneuploidy

mosaicism, which is a mixture of at least two genetically different cell types. Mosaicism in Turner’s syndrome include 45,X/46,XX and 45,X/46,XY[5]. Most cases of turner’s syndrome whether nondisjunction or mosaicism are not inherited. They occur as random events during cell division as the fetus is developing. Monosomy X occurs at random during the formation of gametes in either parent. Nondisjunction occurs during cell division and it results in aneuploidy. Nondisjunction can occur in either meiosis I or meiosis II. If it occurs in meiosis II the chances of a zygote having aneuploidy is less because it results in 2 normal gametes, 1 trisomic gamete, and 1 monomeric gamete. If the mistake occurs in meiosis I it will result in 2 isomeric gametes and 2 monomeric gametes. Therefore, nondisjunction in meiosis I is more prone to having daughter cells with aneuploidy in comparison to nondisjunction in meiosis II. Some studies have shown that mothers who get pregnant at an older age have a higher chance of having children with aneuploidy, but this area needs more research. Turner’s syndrome is seen across all ethnicities and countries with about equal proportions. Though there is no cure for Turner’s syndrome, treatment of symptoms with the use of hormone therapy is available[5]. Biochemical/Molecular Genetic Info/Genotype/Phenotype/Expressivity/Pleiotropy Diagnosis of Turner’s syndrome prenatally can be done with the use of a sonogram and checking maternal serum beta human…

years old. Language, social cognition, and executive functioning were the cognitive functioning domains assessed. To measure the early life stress the Questionnaire of Life Events was utilized. Social cognition on top of executive dysfunction was found in children with an X chromosome to the control group. The number of negative life events was also higher in the children with the X chromosome when compared to the control group. There is a deficiency in the study as to the environmental factors…

What is Plica syndrome? It is an irritation to the synovial membrane in the knee. This irritation is the result of repetitive friction to the tissue. Repetitive friction is due to abnormal forces at the knee, most likely in the kneecap and surrounding musculature, or may be caused by muscular weaknesses or structural abnormalities at the hip or foot, which place increased tension on the knee. “Plica syndrome can also be caused or made worse by increased activities. In some cases, a direct hit…

INTRODUCTION Kallmann syndrome or idiopathic hypogonadotropic hypogonadism with anosmia is a rare genetic disorder having an estimated prevalence of one in 10,000 males and one in 50,000 females. [1] It occurs due to defective hypothalamic migration of GnRH cells from the primitive olfactory placode leading to defective GnRH synthesis and anosmia. [2,3] Accessory breast is a residual breast tissue that persists from normal embryologic development.[4] It can be found in upto 6% of the…

syndrome in honor of his discovery. Nearly a century later, geneticists Jerome Lejeune and Patricia Jacobs reported the chromosomal abnormality for the first time in humans to be secondary to a trisomy of chromosome 21 [1]. The reason that Down syndrome is still so common today is because there has been an increase in older women having babies. Maternal age is an important factor that plays into the possibility of a child being born with Down syndrome. More than half of the pregnancies with Down…

Introduction Dubowitz syndrome was first reported in 1965, by Victor Dubowitz, a British pediatric neurologist. It is a very rare genetic and developmental disorder. According to Huber, Houlihan, and Filter (2011), less than 200 cases have been documented in the literature since it was first reported by Victor Dubowitz in 1965. It is found to present equally in males and females, does not appear to be specific to any particular race or region, but has shown to exist within other members of the…

Background: What is Down Syndrome? Down Syndrome is a chromosomal disorder caused by an error in cell division that results in an extra twenty-first chromosome, that causes birth defects of developmental and intellectual delays. The human body is composed of trillions of cells and within the nucleus of each cell are structures called chromosomes (Parks, 2009). About eight million babies are diagnosed with Down Syndrome in the United States with approximately twenty thousand in Western Europe…

Quentin’s physician believes had has Klinefelter syndrome due to his enlarge breast tissue, long limbs, and abnormally small testes. Based on my findings, “Klinefleter syndrome is a chromosomal condition that affects male physical and cognitive development”(Genetics Home, 2015). This genetic disorder is a result of having 2 X and a Y-chromosomes mixed together. Individuals living with Klinefeter syndrome typically have small testes that do not produce as much testosterone as usual”(Genetic Home,…

Jacobs Syndrome or XYY Syndrome is a genetic disorder where an extra Y chromosome is present in the forty seventh chromosome. The phenotype of the syndrome is normal so there are few to none physical defects. XYY syndrome is sex-linked and only males can be diagnosed with it. This syndrome is livable infact there are some cases where people have the syndrome and never find out until they are older. There are some mental issues that occur from this syndrome. Researchers have not proven but…

Zellweger syndrome (ZS) is an autosomal recessive systemic disorder and is one of four related diseases called Peroxisome Biogenesis Disorders, and is said to occur in 1 in 50,000 individuals. The diseases are caused by defects in any one of twelve genes called PEX genes. (Koroshetz, 2016). Zellweger syndrome is the most severe disease in a subgroup of three similar diseases with overlapping symptoms. Zellweger syndrome is inherited and impairs the proper functioning of the body’s peroxisomes,…