In contrast, a more recent study by Feng et al.27, using Stra8-GFP-Cre and tamoxifen-induced Ddx4-CreERT2 deletion models also targeting exon 6 of Kdm2a, reported reduced testis weight, infertility, and defects in meiotic initiation and progression that was associated with reduced activation of meiotic gene expression in juvenile mice. This evidence concerns the gene STRA8 and Infertility.