Of particular relevance could be the overexpression of NLGN4Y, UTY (also known as KDM6AL or KDM6C), ZFY, and DDX3Y because the non-PAR X (NPX) homologs NLGN4X, KDM6A (also known as UTX), ZFX, and DDX3X, expressed from both X Chromosomes in KS males (Tukiainen et al. 2017), have been previously associated with autism spectrum disorder (ASD), intellectual deficits, developmental delay, and behavioral defects (Jamain et al. 2003; Laumonnier et al. 2004; Lederer et al. 2012; Zhu et al. 2013; Tang et al. 2021; Hoye et al. 2022; Gadek et al. 2023; Shepherdson et al. 2024). The gene discussed is KDM6A; the disease is Global developmental delay.