Molecular Pathology- Miscellaneous I
Question No. 26. The Answer is: (B) Involve the breakage of two chromosomes at or near the centromeres and fusion of their long arms.
Discussion: Robertsonian translocation refers to the translocation and subsequent fusion of the entire long chromosome arms of two chromosomes. The chromosome number is reduced to 45. Robertsonian translocations are seen in about 1:1000 of the general population and in about 3% of patients with Down syndrome. The rearrangement in C describes a reciprocal translocation.