I can’t write a bet­ter lead­ing sen­tence than David already has: “In an arti­cle encour­ag­ing us not to use genetic ten­den­cies for racist ends, William Sale­tan offers a pos­si­ble genetic answer [to the ques­tion, Why are there so many black ath­letes?]”

One exam­ple is the RR vari­ant of ACTN3, a gene that affects fast gen­er­a­tion of mus­cu­lar force and cor­re­lates with excel­lence at speed and power sports. The oppo­site vari­ant of the gene is called XX. Tests indi­cate that the ratio of peo­ple with RR to peo­ple with XX is 1 to 1 among Asians, 2 to 1 among Euro­pean whites, and more than 4 to 1 among African-Americans.