balanced translocation

genetics

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July 16, 2026

Quick Summary

A translocation is a type of chromosomal aberration where a segment of one chromosome breaks off and attaches to a different, nonhomologous chromosome. This occurs when breaks happen in two different chromosomes, and their broken ends then rejoin in a new arrangement.1

While a cell with a heterozygous translocation usually has a complete set of genes and can be viable, it often leads to reduced fertility. This is because during meiosis, the process of creating sex cells, the chromosomes involved in the translocation can segregate abnormally. This can result in gametes that are missing genetic material (deletions) or have extra copies (duplications) of certain chromosome regions, typically leading to inviable offspring.1

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human genetic disease
Calculating risks of known carriers
…if one may be a balanced translocation carrier. Balanced translocations refer to genomic rearrangements in which there is an abnormal covalent arrangement of chromosome segments, although there is no net gain or loss of key genetic material. If both parents exhibit completely normal karyotypes, the recurrence risks cited are low…
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…if one may be a balanced translocation carrier. Balanced translocations refer to genomic rearrangements in which there is an abnormal covalent arrangement of chromosome segments, although there is no net gain or loss of key genetic material. If both parents exhibit completely normal karyotypes, the recurrence risks cited are low…
Read More