It's extremely unlikely that there is any genetic difference that causes people of one particular ethnicity to be more or less susceptible to the effects of the new coronavirus than the people of another ethnicity. And by "extremely unlikely", I mean... no. The fact is that in many ways we are practically identical. If we were that different, medication would be, in general, useless. The fact that our modern pharmaceuticals work as well as they do means that the way our bodies respond to these pharmaceuticals is, essentially, identical. And the way we respond to viruses is in line with the way we respond to medications.
China, Japan and South Korea did not contain the virus because they have a genetic advantage. They contained the virus because they had a governmental advantage.