Mapping of four mouse genes encoding eye lens-specific structural, gap junction, and integral membrane proteins: Cryba1 (crystallin beta A3/A1), Crybb2 (crystallin beta B2), Gja8 (MP70), and Lim2 (MP19).

Four genes encoding eye lens-specific proteins, potential candidate genes for congenital cataract (CC) mutations, were mapped in the mouse genome using a panel of somatic cell hybrids and DNAs from the EU-CIB (European Collaborative Interspecific Backcross). Two of them are lens fiber cell structural proteins: the Cryba1 locus encoding crystallinbetaA3/A1 maps to chromosome 11, 2.5 +/- 2.5 cM distal to D11Mit31, and the Crybb2 locus encoding crystallinbetaB2 maps to chromosome 5, 9.1 +/- 4.3 cM distal to D5Mit88. The other two genes encode lens-specific gap junction and integral membrane proteins, respectively: The Gja8 locus encoding gap juction membrane channel protein alpha8, also called connexin50 or MP70, maps to chromosome 3, 11.9 +/- 5.0 cM distal to D3Mit22, and the Lim2 locus encoding lens intrinsic membrane protein 2, also called MP19, maps to chromosome 7, 2.5 +/- 2.5 cM proximal to Ngfg. All four map positions, when compared with the corresponding positions in human, lie within known regions of conserved synteny between mouse and human chromosomes.