Ring chromosomes: from formation to clinical potential.

Area of Science:

• Genetics
• Molecular Biology
• Human Biology

Background:

• Ring chromosomes (RCs) are rare circular DNA molecules found in eukaryotic genomes.
• First described in fruit flies, human RCs occur in approximately 1 in 50,000 embryos.
• RC carriers may exhibit a range of symptoms, from healthy phenotypes to severe developmental pathologies, often termed "ring chromosome syndrome."

Purpose of the Study:

• To review the inheritance patterns of ring chromosomes.
• To examine the instability and mechanisms of ring chromosome formation.
• To explore potential clinical applications of artificial ring chromosomes for treating large-scale chromosomal rearrangements.

Main Methods:

• Literature review of existing studies on ring chromosomes.
• Analysis of mechanisms including de novo formation via DNA double-strand breaks and inheritance.
• Examination of secondary chromosomal rearrangements caused by RCs.

Main Results:

• RCs arise de novo through various mechanisms or can be inherited.
• RCs are unstable, prone to size changes, loss, or increased copy number.
• Secondary rearrangements like deletions, duplications, and translocations frequently occur in RCs and other chromosomes.

Conclusions:

• Ring chromosomes present complex genetic challenges due to their instability and propensity for secondary rearrangements.
• Understanding RC formation and behavior is crucial for diagnosing and managing associated developmental issues.
• Artificial RCs hold promise for future therapeutic strategies in chromosomal abnormality treatment.