Structural abnormalities include:

Figure 1:Structural chromosome abnormalities

• Deletion: A part of the chromosome is missing or deleted.

• Inversion: A part of the chromosome is broken off, turned upside down and is reattached to the same place. Types of chromosome inversion are:pericentric inversion and paracentric inversion

• Translocation: A part of one chromosome is exchanged with a part of another chromosome. Types of translocation are:Reciprocal and Robertsonian translocation

• Duplication: A part of the chromosome is duplicated, resulting in extra genetic material. Examples:duplication of 9p