A patient with spermatogonial arrest (SPG-1) was in parallel identified with the heterozygous synonymous variant NM_004959.5 c.990G>A p.(Glu330=) in NR5A1, which affects the last base of exon 5 and is also predicted to alter splicing (Wyrwoll et al, 2022). The gene discussed is NR5A1; the disease is hereditary spastic paraplegia.