Pathophysiology—Down Syndrome Introduction

Down Syndrome is a chromosomal disorder that can produce a range of intellectual and physical defects in the individual. Depending on the phenotypic variation, these defects can be more or less severe for some than they are for others (Karmiloff-Smith et al., 2016). It is the most common genetic disorder in the U.S. and the most common cause of learning in young children. It can also lead to other health-related issues and complications such as heart as well as gastrointestinal disorders (Mayo Clinic, 2018). This paper will discuss the pathophysiology of Down Syndrome; the signs, symptoms and complications of the disorder; what current research and evidence-based practices focus on; and the most common treatment and management practices for Down Syndrome.



Pathophysiology

In all but 5% of cases, Down Syndrome is caused by trisomy 21—i.e., the individual has three chromosome 21 copies (Antonarakis, Lyle, Dermitzakis, Reymond & Deutsch, 2004). As human cells typically have 23 chromosome pairs, with the father...

Down Syndrome is caused by a disruption in the 21st chromosome: the cell of this chromosome abnormally divides; the result is that more genetic material is developed than is needed and that can negatively impact the features of the child and the development of the child’s cognitive abilities in some cases.
While Trisomy 21, or three full copies of chromosome 21, is most commonly the cause of Down Syndrome for about 95% of the cases, other forms are possible: Mosaic Down Syndrome and Translocation Down Syndrome are the two other possibilities. In the former, the extra copy of chromosome 21 is only found in a few of the child’s cells rather than in all. In the latter, chromosome 21 attaches to a separate chromosome. Currently, the exact cause of this disruption in chromosome 21 is unknown (Mayo Clinic, 2018). However, risk factors that have been identified include the age of the mother at conception—the risk is greater when the woman is over the age of 35.

Signs, symptoms and complications

Diagnoses can be made before as well as after birth. Signs of intellectual disability may indicate Down Syndrome, as most individuals with this genetic disorder display some form of…