chromosomal mutation that flips a segment of the chromosome
The chromosomal mutation you are referring to is called an "inversion." An inversion occurs when a single chromosome undergoes breakage and rearrangement within itself. Essentially, a segment of the chromosome is flipped end to end and reinserted into the chromosome at the original location, so that the gene sequence within that segment is reversed compared to the normal sequence.
There are two types of inversions:
1. Pericentric inversion: This type includes the centromere within the inverted segment. The breakage points occur in both arms of the chromosome, one above and one below the centromere.
2. Paracentric inversion: This type does not include the centromere and occurs when the breaks are both in one arm of the chromosome.
Inversions can be balanced or unbalanced. A balanced inversion occurs when the inversion does not involve the loss of genetic information, but simply rearranges the genomic sequence. Individuals with a balanced inversion typically do not show any symptoms because all genetic material is present, just rearranged.
Unbalanced inversions can lead to duplications or deletions of genetic material, which can cause developmental issues or other phenotypic abnormalities depending on the genes affected.
In meiosis, inversions can lead to challenges during the pairing of homologous chromosomes, potentially resulting in recombinant chromosomes that have duplications and/or deletions. This can result in fertility problems or lead to genetic disorders in offspring, particularly if the chromosomes don't segregate properly during cell division.