An association hit points to a single gene as the proven cause.

Circle one:   True   False

What does a genome wide association study scan for?

• One gene that fully causes each disease
• The exact birthday of each mutation
• Positions where one version is more common in affected people

Why do these studies need a far stricter significance threshold?

• Computers demand round numbers
• Journals prefer small p values aesthetically
• A million tests make thousands look linked by luck

You carry a variant tied to a trait. What does that mean?

• You will certainly develop the trait
• Your children are immune to it
• Your risk shifts a little; most carriers stay unaffected

Why does a hit blur across a region instead of one address?

• Linkage: neighbours are inherited together as a block
• Sequencers cannot read single positions
• Alleles refuse to be counted

What narrows an association block to the causal change?

• Fine mapping plus lab tests on the gene
• Repeating the same scan louder
• Deleting the whole chromosome

How do researchers move from a hit to a cause?

• Assume the nearest gene is guilty
• Fine map the block and test the gene in the lab
• Scan even more people forever

A company predicts your disease from one associated variant. Why refuse the reading?

• Population patterns never verdict an individual outcome
• DNA has nothing to do with disease
• Only doctors may look at DNA