SOX9 and polygenic risk score: This paradigm parallels another SOX gene close to SOX10, SOX9. The involvement of the latter in campomelic dysplasia (CD) was demonstrated 17 years ago [32], [33], but long distance genomic alterations at this locus have been recently associated with isolated disorders of sex development as well as isolated Pierre Robin sequence (PRS), both typical features of CD [34], [35], [36], [37].