translocation Down syndrome

medical condition

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Last updated

July 19, 2026

Quick Summary

Translocation Down syndrome is a genetic disorder where an extra part of chromosome 21, or an entire extra copy, attaches to another chromosome. This differs from the most common form, trisomy 21, where all cells have three copies of chromosome 21. Translocation Down syndrome is the only type that can be inherited, typically from a parent carrying a balanced translocation without symptoms. While carriers don't show signs, they have a risk of passing it to offspring. This condition results in developmental delays and characteristic physical features, with impacts varying in severity.1

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Down syndrome
Types of Down syndrome
The third type, translocation Down syndrome, occurs when the extra chromosome in the 21 pair breaks off and attaches itself to another chromosome. Translocation Down syndrome is the only type that may be inherited. A parent who possesses a balanced translocation—a chromosome rearrangement with no extra genetic material…
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The third type, translocation Down syndrome, occurs when the extra chromosome in the 21 pair breaks off and attaches itself to another chromosome. Translocation Down syndrome is the only type that may be inherited. A parent who possesses a balanced translocation—a chromosome rearrangement with no extra genetic material…
Read More