Three known microphthalmia alleles (Mfrp<sup>rd6</sup>, Prss56<sup>glcr4</sup>, and Adipor1<sup>tm1Dgen</sup>) and two prospective alleles (C1qtnf5<sup>tm1.1(KOMP)Vlcg</sup> and Prss56<sup>em2(IMPC)J</sup>) were introgressed onto the C57BL/6J (B6) genetic background and compared to B6 mice at 1 through 12 months of age. Here, PRSS56 is linked to microphthalmia.