Structural Abnormalities

Question 1

Why are individuals who carry a balanced rearrangement at risk of having a child with an imbalance?

Answer 1

In carriers, nonhomologous material may pair (heterozynapsis) and segregate at meiosis as normal, or homologous segments of rearranged chromosomes will align (homosynapsis) due to their inherent tendency to pair. Both predispose to unbalanced segregation. Carriers of inversions or insertions may produce a new recombinant.

Question 2

Define a translocation

Answer 2

When a chromosomal segment is moved from one position to another, within the same chromosome or to another chromosome.

Question 3

Define types of inversions

Answer 3

Pericentric and Paracentric.