Down Syndrome Essay

Down Syndrome (DS) is a chromosomal disease affecting tens of thousands of individuals. DS is responsible for a wide range of health disorders, including, but not limited to, congenital heart disease, cancers, Alzheimer’s, and other phenotypic abnormalities (Asim et al., 2015). Given its relatively high prevalence (1 in 900 births) in some locations, the impact of DS is high (Shin et al., 2009). Trisomy 21, Mosaic Down Syndrome, and Translocation Down Syndrome are three instances of abnormalities in chromosome 21 replication. At 95% prevalence among DS patients, Trisomy 21 is the possession of a third 21st chromosome causes the genes present to be expressed at different rates compared to non-DS cohorts.
Human chromosome 21 (HSA21) failure to segregate during oocyte meiosis I, also known as nondisjunction, is the leading cause of DS. The result of nondisjunction is aneuploidy. Evidence supports nondisjunction in HSA21 of oocytes increases with increasing age due to single or absent segregation in the telomeric region, or spindle malfunction (Oliver et. al, 2008). Spindle formation has been shown to
General mechanisms of these diseases were outlined by Asim, et al. Cardiac defects arise from septal deformations caused by failure of cell adhesions. GI obstruction is the direct result of absence of myenteric innervation in the colon. The lack of innervation causes drop in neurotransmitters necessary for proper contraction and resulting peristaltic movement. The prevalence of blood disorders is associated with mutations in the GATA-1 gene that is involved in blood cell differentiation. Studies by Kyttala et al., (1994) showed Down Syndrome Critical Region 1, a hematological negative-feedback regulator, overexpression impairs downstream regulation of blood cell