GJA8 and cataract: The No2 mouse carries a missense mutation within the coding region of Cx50 resulting in a change of amino acid residue 47 from aspartate to alanine (Cx50D47A) and develops congenital cataracts (Favor, 1983; Steele et al., 1998); these cataracts are less severe in heterozygous than in homozygous animals.