Nature or nurture?
This topic tends to be quite political—it’s hard to find even-handed writing on the subject. We can mostly only measure loose indicators, but be careful of the distinction between what’s being measured and what’s being claimed. For instance, Ericsson et al (1993, p. 364–365) present various non-associations between ability tests and expertise, but that’s not at all the same as demonstrating heritability.
Ericsson et al argue (1993, p. 365): exceptional performance doesn’t generalize -> acquired knowledge and skill are important to expertise -> exceptional ability isn’t heritable. I don’t think this holds, because heritable traits could help people acquire non-transferable skills more effectively.
Related: Growth mindset
Q. What’s an important class of exceptions to the general observation that talent can’t be explained by heritable traits?
A. Sports: height, muscle fiber type distributions, and other highly relevant traits are heritable.
Q. How might small heritable variations in ability be amplified into large differences in adult expertise?
A. A child might perform better at something without training due to some heritable trait, which might lead to more practice, hence more expertise.
Coyle, D. (2009). The Talent Code. Bantam Books.
Ericsson, K. A., Krampe, R. T., & Tesch-Römer, C. (1993). The role of deliberate practice in the acquisition of expert performance. Psychological Review, 100(3), 363. Ericsson et al - The Role of Deliberate Practice in the Acquisition of Expert Performance