Variants in genes involved in gonadal development (e.g. SRY (Berta et al. 1990; Sinclair et al. 1990), steroid hormone biosynthesis (e.g. 5α-reductase deficiency) or androgen responsiveness give rise to various forms of 46,XY DSD that may result in a female appearing, or predominantly female appearing, phenotype (Berta et al. 1990; O’Connell et al. 2021). This evidence concerns the gene SRY and disorder of sexual differentiation.