Whites do not have the highest mean IQ.
From what I have read some Jewish groups have upwards of 110 score in IQ and even though the Jewish population is very small they have 25% of Noble Peace awards.
The White Asians are next on the list with a mean score of 105 IQ points. We see the rise of China and remember south Korea devastated 60 years ago but now a technological marvel in a short time.
Whites come in next with 100 points IQ. The IQ test based originally on whites to test under performing children by a French Psychologist over 100 years ago.
Some points to consider are
Identical twins have been tested that have been separated early in life one to a rich family and the other to a poor family but both when tested show very close IQ scores.
A persons IQ is not reliant on education level .
Nutrition is a factor for brain development and can effect IQ scores.
IQ scores are according to Psychologists the most reliable data when accessing a person.
I once saw a video where school children in India are accessed every year to see if the smarter ones can qualify for a scholarship. Once IQ is established it is fixed for life. Some consideration is allowed for old age.