Effects Of Intergenerational Mobility

In the U.S., children born to the families in the poorest 20 percent of the income distribution have barely about 9 percent of chances to rise to the richest 20 percent as adults for the last two generations (Chetty et al. 2014). While the figure remains stable for the 1970-80s birth cohorts, recognition of the unequal intergenerational mobility of the U.S. society has increased lately. The upward and downward intergenerational mobility occurs depends largely on both parental and children’s educational attainment (Blau and Duncan 1967). However, although social scientists interpret the transmission of educational attainment mainly through social inheritance, it is arguable that genetic heritability also plays a role in the mobility process (Eckland 1967; Duncan 1968; Behrman and Taubman 1989; Jencks and Tach 2006; Nielsen 2006; Nielsen and Roos 2015).

Past studies using twins and siblings to address the issue were not able to account for the specific genetic effects due to the unclear identification of the shared genes, and the difficulties to distinguish genetic effects from environmental effects because the identical twins are more likely to pursue alike environment more than fraternal twins do. Therefore, by incorporating the polygenic score of education, a measure that summarizes the effects of specific genetic variants that are associated with education, this study attempts to answer the question