Race is genetic. Most just refuse to accept the science. But ultimately it's who your ancestors were. Who is your extended family? Under that rubric, neither Obama or Harris are Black Americans as understood to be descended from American slaves. But so what? Didn't affect Obama.
American slaves were from West Africa. Obama's father was from Kenya in East Africa. I remember discussions that Obama didn't represent the American Black experience because of this. That his ancestors weren't slaves in America. It is not surprising to me that the people who suffered under racism consider the concept of racism to be valid because it has been for them. But it doesn't prove the scientific validity of the concept.
Of course, the characteristics that are used to define the races are genetic; skin color, the shape of the nose, eye hoods, etc. It is using these characteristics to define different so-called races that are social constructs. There are many different physical characteristics that are different between different people, many of which aren't used to define different types of human beings. What is so special about the physical characteristics used to define race?
If you divided human beings by eye color and said that people with blue eyes were inferior to the majority of brown-eyed people, that blue-eyed people were lazy and shiftless and weren't worth educating, were only suitable for manual labor, and weren't worth studying by science, it wouldn't take many generations acting on these beliefs before you could prove the concept of the inferiority of the blue-eyed people in the same "scientific" way as you propose proves the validity of racism. The blue-eyed people would be adept physically but not intellectually and prone to many diseases not understood by modern science.
We don't define people with different colored eyes as different types of people like we do people with different skin tones. What is different about skin tones that they define so many different behaviors?
As to your link above about misclassifying cancer cells, it isn't surprising that susceptibility to certain diseases is genetically based too. You imply that this proves that the concept of race has a basis in genetics and therefore in science. This is turning logic onto itself. You are defining race and then assuming the definition is true to prove that it is true.
All that the study is saying is that we have to collect a wider genetic sample of cancer cells to be assured of covering all of the existing susceptibilities to cancer in humans. The concept of race is what prevented the required range of sampling so that it is not surprising they use the language of race to correct the problem. But it doesn't prove the concept. Once again, this is circular reasoning.