“…For rare variants, a problem of the traditional additive models is that it is hard to estimate the effects of all genetic variants because the number of genetic terms in the regression model can be large, and the related tests can be less powerful. The fixed-effect FR models are based on population genetics theory and model the contribution of genetic variants as an unknown function of physical position [Fan et al, 2013[Fan et al, , 2014[Fan et al, , 2016a[Fan et al, , 2016bLuo et al, 2011Luo et al, , 2012Luo et al, , 2013Vsevolozhskaya et al, 2014;Wang et al, 2015;Zhang et al, 2014;Zhao et al, 2016]. The fixed-effect FR models can analyze rare variants or common variants or a combination of the two.…”