Sure they do.
"Everyone is equal and nobody has a genetic advantage/difference etc. etc."
You know how it goes. Usually the request is made to "name those genes" and the articles studying those differences actually do list many of the genes and try to pinpoint other genes that are different or expressed differently.
Crack a book or read some of the studies online.
That isn't true. There are no studies that have found any running genes. At most, some studies found correlations. Until they actually find a causal relationship, you can't say whether anyone has or does not have a genetic advantage.
There may not be a running gene. However, simple data analysis clearly shows East Africans are faster than the rest of the distance running world. In addition studies have shown that East Africans have skinnier legs and their ratio of leg length to overall height is larger than the Caucasian world. The two later points are clearly genetic and clearly correlate to better running efficiency. Just as a Ford Mustang is built for speed and efficiency as compared to a Ford F250.