Written By Shresta Majeti
Genetics
Based on current genetic research, Down syndrome, a complex genetic condition, is primarily attributed to an arbitrary error known as nondisjunction during cell division. Nondisjunction occurs when something goes amiss, causing chromosomes from one pair to go into one cell, while no chromosomes from that pair go into the other cell. This phenomenon results in the presence of an extra copy of chromosome 21, a condition referred to as trisomy 21. Trisomy 21 appears during the formation of either the egg or sperm, and it is significant to note that no specific behavioral activities of the parents or environmental factors have been identified as causing Down syndrome. Trisomy 21 is the predominant form, accounting about 95% of Down syndrome cases, and it is associated with distinctive physical features and developmental challenges (CDC, 2023).
In addition to trisomy 21, another cause of Down syndrome is chromosomal translocation, albeit constituting for a smaller proportion of cases. In translocation Down syndrome, a segment of chromosome 21 breaks off and binds itself to another chromosome, often chromosome 14. Despite the total number of chromosomes remaining at 46, the presence of additional genetic material can cause havoc to normal development, resulting in the characteristic features associated with Down syndrome. Strangely, translocation Down syndrome can be inherited, typically occurring when one of the parents carries a rearrangement of genetic material involving chromosome 21. Individuals with translocation Down syndrome do not exhibit significant differences compared to those with the more common trisomy 21, emphasizing the complexity of these genetic variations.
Mosaicism represents a less frequent cause of Down syndrome, characterized by an individual having a mixture of cells with the typical two copies of chromosome 21 and others with three copies. This genetic variation arises from mistakes in cell division that occur after fertilization. The existence of mosaicism introduces variance in the severity of Down syndrome features among affected individuals. This mosaic pattern contributes to the diverse clinical presentations observed in individuals with Down syndrome. Understanding the role of mosaicism adds another layer of complexity to the genetic mechanisms underlying Down syndrome and highlights the importance of considering individual differences in the manifestation of this condition(Johnson, 2020)
Maternal Age
While the genetic basis is the primary cause, maternal age is a significant risk factor. The likelihood of having a child with Down syndrome increases with maternal age, particularly after the age of 35. However, it’s crucial to acknowledge that individuals of all ages can have children with Down syndrome, and the majority of babies with Down syndrome are born to mothers under the age of 35. Advanced maternal age is associated with an increased chance of errors in chromosome division during egg formation, contributing to the higher incidence of Down syndrome in older mothers (CDC, 2023)
Treatments
It is crucial to understand that, as of now, there are no cures for Down syndrome. Nevertheless, it becomes vital to acknowledge the significance of offering comprehensive support and care for individuals diagnosed with Down syndrome, as well as their families. The range of Down syndrome care is evolving, with ongoing research endeavors aimed at intensifying our understanding of the condition and exploring innovative therapeutic approaches. By recognizing the complex needs associated with Down syndrome, the medical and scientific communities strive to augment the quality of life for those affected.
The absence of a cure underscores the imperativeness of early intervention, educational resources, and access to healthcare services in the management of Down syndrome. Early recognition of developmental challenges and prompt intervention can significantly improve developmental outcomes. Educational resources personalized to the unique learning profiles of individuals with Down syndrome contribute to their cognitive and academic growth. Access to comprehensive healthcare services guarantees that medical needs are addressed in a timely manner, stimulating overall well-being (Sachdev, 2017).
References
default - Stanford Medicine Children’s Health. (n.d.). https://www.stanfordchildrens.org/en/topic/default?id=translocation-down-syndrome-90-P02153
Down syndrome. (2017, April 12). WebMD. https://www.webmd.com/children/understanding-down-syndrome-basics
Down syndrome - Symptoms and causes - Mayo Clinic. (2018, March 8). Mayo Clinic. https://www.mayoclinic.org/diseases-conditions/down-syndrome/symptoms-causes/syc-20355977
Facts about Down Syndrome | CDC. (2023, October 10). Centers for Disease Control and Prevention. https://www.cdc.gov/ncbddd/birthdefects/downsyndrome.html
What causes Down syndrome? (2023, November 30). https://www.nichd.nih.gov/. https://www.nichd.nih.gov/health/topics/down/conditioninfo/causes#:~:text=Down%20syndrome%20is%20caused%20by,of%20error%20is%20called%20nondisjunction.
Johnson, J. (2020, March 25). What is mosaic Down syndrome? https://www.medicalnewstoday.com/articles/mosaic-down-syndrome#characteristics
Comments