 Finally, heritability is unequivocally tethered to bioethics. To the extent that twin heritability estimates played a central role in debates about race science from the 70s through the 90s, the advent of SNP heritability warrants a renewed assessment. Just as it was for twin heritability, SNP heritability is now being used to assess old, controversial questions about the genetic basis of racial differences in intelligence and cognitive ability. Presumably because twin heritability and SNP heritability are conceptually and methodologically distinct, there is demand for philosophers and scientists to re-assess the legitimacy of group-difference investigations that appeal to SNP heritability.