Down syndrome

What is Down Syndrome?

Down syndrome is a genetic disorder caused by the presence of an extra copy of chromosome 21 (Trisomy 21). It affects physical growth, intellectual development, and overall health.

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Types of Down Syndrome:

1️⃣ Trisomy 21 (Most Common – 95%)
🧬 Every cell in the body has an extra chromosome 21.

2️⃣ Mosaic Down Syndrome (Rare – 1%)
🧬 Some cells have an extra chromosome, while others have a normal count.

3️⃣ Translocation Down Syndrome (4%)
🧬 A part of chromosome 21 attaches to another chromosome.

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Physical Features of Down Syndrome:

👶 Flattened facial features
👀 Upward-slanting almond-shaped eyes
👅 Small mouth with a protruding tongue
🖐 Single deep crease across the palm
🦵 Shorter height & low muscle tone (hypotonia)
👂 Small ears & short neck

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Causes & Risk Factors:

🧬 Genetic Abnormality – Extra chromosome 21 occurs randomly.
🤰 Advanced Maternal Age – Risk increases in pregnancies after 35 years.
👪 Genetic Inheritance (Rare) – Some cases of translocation Down syndrome are inherited.

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Common Health Issues in Down Syndrome:

❤️ Congenital Heart Defects – Common in 50% of cases.
🧠 Intellectual Disability – Mild to moderate learning difficulties.
🦵 Low Muscle Tone (Hypotonia) – Delayed motor development.
👀 Vision Problems – Cataracts, nearsightedness.
👂 Hearing Loss – Due to frequent ear infections.
🦴 Thyroid Disorders – Hypothyroidism is common.
🛌 Sleep Apnea – Breathing difficulties during sleep.