GWAS is nothing more than correlations and by themselves aren't very remarkable. What is remarkable is when someone does a functional analysis on the variant they found in their GWAS and is able to describe the mechanism that it uses to affect the disease or phenotype. The way you do that isn't more sequencing, but with model systems that you can easily manipulate in the lab.
GWAS also doesn't compare to an arbitrary reference sequence. Some good numbers for a GWAS are >1000 cases and >2000 controls from the same population. You have to match populations, or else all your association study is going to find is the differences between east asians and europeans, for example. You need a lot of samples to get enough stats power to even see these rare variants.
GWAS also doesn't compare to an arbitrary reference sequence. Some good numbers for a GWAS are >1000 cases and >2000 controls from the same population. You have to match populations, or else all your association study is going to find is the differences between east asians and europeans, for example. You need a lot of samples to get enough stats power to even see these rare variants.