ESR1 and lupus nephritis: These data in the NZM2410 and MRL-lpr strains are in sharp contrast to what we observed in the (NZB × NZW)F1 hybrid model, in which the attenuation of lupus nephritis due to the Esr1tm1Ksk allele (knockout of full length ERα) in female mice was associated with a significant decrease in anti-dsDNA IgG and anti-chromatin IgG autoantibodies (12).