Talented & Gifted programs are specifically high-IQ (as they're based on the same rules that set up special education classes for low-IQ students).
IQ tests have been shown to be culturally biased (and thus indirectly racially biased), as there's an assumption that people will have certain cultural knowledge & norms.
Take for instance the question "What are the four seasons?". For someone in Alaska, when they hear 'seasons' they might not think about the winter/spring/summer/autumn cycle, but might instead respond with hunting/trapping periods (moose, fishing, etc.).
Questions about nature might be easy for someone who lives in a rural or suburban area, but more difficult for someone who lives in an inner-city.
Questions about place settings at a dinner table (eg, cup & saucer) might be easier for someone from a higher socio-economic group than for someone who is food-insecure.
These may not be direct racial bias, but they can negatively skew test scores for people of non-European descent.