Deletion of meiosis-specific cohesin subunits in mice (Rec8−/−, Smc1b−/− and Rad21L−/−) showed defects in synapsis and infertility (Bannister et al. 2004; Revenkova et al. 2004; Xu et al. 2005) and premature reproductive senescence in Rad21L−/− females associated with a defect in primordial follicles (Herran et al. 2011). Here, SMC1B is linked to Infertility.