SQOR and Leigh syndrome: A potential limitation of this study is that the genetic mutation in SqorΔN/ΔN mice (homozygotes for 14-bp deletion of CCTGGTGATGGCCC at exon 2 of the SQOR gene) differed from that in Leigh syndrome patients (homozygotes for the pathogenic variant c.637G>A or c.446delT) (9, 13).