Which condition is also known as Trisomy - 21? - RRB Nsg. Superintendent-20 July 2019 (Shift-3rd)

RRB Nsg. Superintendent-20 July 2019 (Shift-3rd)

Pathology & Genetics

Easy

Appeared in: RRB Nsg. Superintendent-20 July 2019 (Shift-3rd)

Explanation

Down Syndrome is the correct answer as it is medically known as Trisomy 21.
This condition is characterized by the presence of a third copy of chromosome 21, resulting from an error in cell division (nondisjunction).
The extra genetic material is responsible for the distinct physical and developmental traits of Down Syndrome.
It is the most common chromosomal disorder, occurring in approximately 1 in 800 to 1,000 live births.

Option A: Cushing Syndrome is an endocrine disorder, not a genetic one. It is caused by excess cortisol in the body.
Option B: Addison's disease is an endocrine disorder involving adrenal insufficiency (low cortisol and aldosterone), not a chromosomal abnormality.
Option C: Graves' Disease is an autoimmune disorder that causes hyperthyroidism (overactive thyroid). It is not related to chromosomal trisomy.

Visual 1: Karyotype Diagram - A human karyotype clearly showing three copies of chromosome 21, visually explaining the term 'Trisomy 21'.
Visual 2: Infographic - An infographic illustrating the common physical characteristics of a person with Down Syndrome, such as a flat facial profile, upward slanting eyes, and a single palmar crease.
Visual 3: Comparison Chart - A chart comparing the causes of Down Syndrome (genetic), Cushing Syndrome (hormonal), Addison's Disease (hormonal), and Graves' Disease (autoimmune) to clarify their different origins.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Genetic Disorders and Chromosomal Abnormalities as background academic context rather than a clinical decision trigger.
Nurses play a crucial role in supporting families of children with Down Syndrome, from initial diagnosis and counseling to coordinating care for associated health issues like cardiac defects and hypothyroidism.
Early intervention is key. Nurses can educate parents on therapies such as speech, physical, and occupational therapy to help children with Down Syndrome reach their full potential.
What if? If a prenatal screening test (like a nuchal translucency scan or maternal serum markers) indicates a high risk for Down Syndrome, the next step is not immediate diagnosis but offering further diagnostic testing, such as amniocentesis or chorionic villus sampling (CVS), for a definitive karyotype analysis. The nurse's role is to explain these options and provide support.

How to Approach the Question

First, identify the core term in the question: 'Trisomy - 21'.
Recognize that 'tri-' means three and '-somy' refers to a chromosome. Therefore, the term means 'three copies of chromosome 21'.
This is a factual recall question. You need to access your knowledge of genetic disorders and their common names.
Evaluate the options. Cushing, Addison's, and Graves' are all well-known endocrine or autoimmune disorders, not chromosomal abnormalities.
Recall or deduce that Down Syndrome is the specific genetic condition caused by an extra 21st chromosome.
Select Down Syndrome as the correct synonym for Trisomy 21.

Concept Tested & Keywords

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