Previously, a child with a pathogenic variant in the testis-determining factor NR5A1 (p.V355M) was reported, who presented with bilateral anorchia and reduced penile length; however, his dizygotic twin brother was also heterozygous for the change yet had normal development, suggesting that other genetic factors may be involved.32 Here, we found that 25% of children with clinically well-defined TRS carried pathogenic variants in the DHX37 gene. The gene discussed is NR5A1; the disease is Testicular regression syndrome.