Final answer:
A Robertsonian translocation occurs when two acrocentric chromosomes join at their centromeres, resulting in a rearrangement of genetic material. This can result in chromosomal abnormalities and birth defects, depending on the specific rearrangement and chromosomes involved.
Step-by-step explanation:
A Robertsonian translocation occurs when two acrocentric chromosomes, which have very short arms, join at their centromeres, resulting in a rearrangement of genetic material. This type of translocation is most commonly seen in humans between chromosomes 13 and 14, or chromosomes 14 and 21.
This type of translocation can be inherited or occur spontaneously. Inherited Robertsonian translocations have a higher risk of resulting in chromosomal abnormalities and birth defects. However not all individuals with Robertsonian translocations will have health issues as it depends on which chromosomes are involved and the specific rearrangement of genetic material.