Robertsonian Translocations & Correlation to Down Syndrome

The video discusses Down syndrome, primarily caused by nondisjunction events, and less commonly by robertsonian translocations. It explains the genetic mechanisms, including chromosome anatomy and the role of acrosomal chromosomes. The video highlights that while nondisjunction is the main cause, robertsonian translocations are clinically relevant. The mechanism of Down syndrome remains an active research area.

What is the most common cause of Down syndrome?

• Nondisjunction event

• Environmental factors

• Robertsonian translocation

• Gene mutation

What percentage of Down syndrome cases are caused by Robertsonian translocation?

• 20-25%

• 2-4%

• 5-8%

• 10-15%

In which cells does Robertsonian translocation occur?

• Somatic cells

• Neurons

• Muscle cells

• Germline cells

What is an acrosomal chromosome characterized by?

• No centromere

• Equal length arms

• A very short P arm

• A centromere in the middle

What happens during a Robertsonian translocation?

• Chromosomes duplicate

• Chromosome fragments break and join

• Genes mutate

• Chromosomes disappear

Why are Robertsonian translocations clinically relevant despite their rarity?

• They are the most common cause of Down syndrome

• They affect all somatic cells

• They can lead to other genetic conditions

• They have no impact on offspring

What is still unknown about Down syndrome's mechanism?

• How three copies of chromosome 21 cause symptoms

• The role of environmental factors

• The impact of diet on the condition

• The exact number of chromosomes involved