In genetics, what is a paracentric inversion?

A paracentric inversion refers to a specific type of chromosomal rearrangement in which a segment of a chromosome is reversed in orientation. This inversion occurs only within one arm of the chromosome, meaning it does not involve the centromere. In a paracentric inversion, the inverted segment does not cross over to the other arm of the chromosome, thus distinguishing it from other types of inversions that involve both arms, which are classified as pericentric inversions.

Understanding the structural changes caused by paracentric inversions is important in genetics, particularly in the context of meiosis and potential implications for gamete viability. If a crossover occurs in a paracentric inversion during meiosis, it can lead to the production of gametes that may not be viable due to the generation of acentric fragments or dicentric chromosomes.

This knowledge is crucial for interpreting genetic abnormalities and their potential effects on development and health.