A Comprehensive Review of Down Syndrome:

Molecular Basis, Clinical Characteristics and Therapeutic Prospects

Veerabhadrappa G Mendagudli

Principal, BLDEA’S College of Nursing, Jamkhandi. Karnataka, India.

*Corresponding Author E-mail: veerabhadrappa.bijapur@gmail.com

ABSTRACT:

Trisomy 21—another name for Down syndrome—is a genetic disease brought on by the presence of an extra copy of chromosome 21. Physical, mental, and developmental traits are produced as a result of this increased genetic material. Common facial characteristics of people with Down syndrome include almond-shaped eyes and a flat nasal bridge. In addition to having a higher risk of developing certain medical diseases, such as heart defects, hearing loss, and thyroid disorders, they may also face delays in their motor and cognitive development. Down syndrome sufferers often have mild to moderate intellectual handicap, while their cognitive abilities can vary greatly. They can greatly improve their quality of life and reach their full potential with early intervention, specialised education, and supportive environments. The quality of life for those with Down syndrome is improving, and they are making a variety of contributions to their communities thanks to changes in medical treatment and societal views. Down syndrome's impacts on brain function and development are still being better understood through research into the basic factors that underlie it. The goal of these efforts is to develop tailored therapeutics to enhance cognitive and developmental outcomes by better understanding the genetic and molecular components that contribute to the condition. Overall, research into, advocacy for, and support for people with Down syndrome continues. These efforts are aimed at advancing inclusivity, equal opportunity, and a greater understanding of neuro diversity¹

KEYWORDS: Down Syndrome (DS), Trisomy 21, Chromosomes, Genetic Disorder, Genetic Counsellor

INTRODUCTION:

The most prevalent chromosomal condition, Down syndrome affects around 1 in 700 live babies globally. It is characterised by a variety of cognitive, physical, and developmental difficulties. The existence of three copies of chromosome 21(trisomy 21), which results from a mistake during cell division, is the main genetic cause of Down syndrome. The distinctive traits of down syndrome are caused by the addition of genetic material. People with Down syndrome can contribute to a variety of groups and have special talents. Their quality of life is being improved, and research is being done to better understand how genes affect human development².

Genetic foundation:

A full or partial extra copy of chromosome 21 comes from faulty cell division, which is the genetic disease known as Down syndrome. Developmental abnormalities and physical characteristics of Down syndrome are brought on by this excess genetic material.

Down syndrome can cause developmental delays and intellectual disabilities that last a lifetime, depending on an individual's level of severity. It is the most typical hereditary chromosomal disease and the main contributor to learning impairments in kids. It frequently results in heart and gastrointestinal problems as well as other medical issues³.

The quality of life for children and adults with this illness can be considerably improved, and they can lead full lives with the support of early interventions and better awareness of Down syndrome⁴.

Trisomy 21 primarily develops as a result of nondisjunction during either maternal or paternal meiosis, which causes an uneven distribution of chromosomes during cell division. The mechanisms driving nondisjunction and the contribution of particular genes on chromosome 21 to the DS phenotype have been revealed through advances in genetic research⁵.

Clinical Features:

Some of the notable clinical features of Down syndrome include:

1. Recognizable Facial Features: People with Down syndrome frequently exhibit facial characteristics that are easy to spot, such as almond-shaped eyes, a flat facial profile, a small nose with a flat bridge, a projecting tongue, and a small chin.

2. Cognitive and Developmental Delays: Intellectual and developmental delays are linked to Down syndrome. People with Down syndrome often have mild to severe cognitive impairment, which causes delays in language development, learning challenges, and motor skill development.

3. Muscle Hypotonia: People with Down syndrome frequently have lower muscle tone, which gives them a floppy or loose appearance. This may have an impact on physical development, coordination, and motor abilities.

4. Short Stature: Compared to the general population, people with Down syndrome typically have shorter statures. Growth hormone therapy occasionally aids in addressing this issue.

5. Heart problems: Congenital heart problems, which can range in severity from moderate to severe and call for medical attention, are common in people with Down syndrome.

6. Digestive Issues: People with Down syndrome are more likely to experience digestive issues such gastrointestinal obstructions.

7. Hearing and Vision Issues: People with Down syndrome are more likely to have hearing impairments and visual problems like cataracts and refractive errors.

8. Thyroid Dysfunction: People with Down syndrome are more likely to experience thyroid issues, especially hypothyroidism, which calls for monitoring and treatment.

9. Increased Susceptibility to Infections: Due to immune system variations, individuals with Down syndrome may be more vulnerable to respiratory infections and other ailments.

10. Dental Concerns: People with Down syndrome frequently experience dental issues, such as delayed tooth eruption and an increased risk of gum disease.

11. Neurological Disparities: People with Down syndrome may encounter neurological difficulties that affect their cognitive functioning, linguistic development, and fine motor skills.

12. Behavioural features: People with Down syndrome are more likely to exhibit certain behavioural traits, such as social friendliness, empathy, and a penchant for routine.

While these clinical features are frequently linked to Down syndrome, it's crucial to remember that there is substantial individual variance. Down syndrome sufferers' quality of life can be significantly enhanced by early intervention, specialised education, and medical treatment, which can also assist them in overcoming obstacles and realising their full potential⁶.

Therapeutic Prospects:

Recent advancements in medical and therapeutic approaches have demonstrated potential for enhancing the general well-being of people with DS. Developmental advancement can be aided by early interventions like speech and occupational therapy. Additionally, continuing studies into pharmaceutical therapies that target memory and cognitive deficits may provide possible therapeutic routes⁷.

Prevention

Down syndrome cannot be avoided. A genetic counsellor should be consulted before to conception if you are highly likely to have a child with Down syndrome or if you currently have a child who has the condition. You can learn more about your likelihood of becoming pregnant with a Down syndrome child from a genetic counsellor. Additionally, he or she can discuss the different prenatal tests with you and help you weigh their benefits and drawbacks⁸.

CONCLUSION:

Down syndrome continues to be a challenging genetic condition with a wide range of clinical ramifications. The quality of life for people with DS and their families is continually being improved by developments in genetic understanding, medicinal therapies, and supportive services. Despite advancements in science, meeting the particular needs of those with down syndrome still requires a comprehensive strategy that includes medical, educational, and social care.

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Received on 21.08.2023 Modified on 29.01.2024

Int. J. of Advances in Nur. Management. 2024; 12(2):99-100.

DOI: 10.52711/2454-2652.2024.00022