How to check for a variant (like *3) in public HepG2 cell line?

Question

[Pin.Bioinf]

Hello, I was requested to check for a specific gene *3 variant in public datasets in cell line HepG2. From my understanding, I believe I need to download .fastq files and check for that gene in IGV program visualizer or maybe dirrectly check if there are already variants for cell line HepG2 available and check if my variant is there?

In summary: need to know where to look for that information. Genotyped HepG2 might be a good choice? Where can I find it?

Thank you