Among these genes, the crystallin and connexin genes appear to be the most commonly associated with congenital cataracts, whereas approximately half of the mutations belong to the crystalline genes (CRYAA, CRYAB, CRYBA1/A3, CRYBB1, CRYBB2, CRYBA4, CRYGC, CRYGD and CRYGS) and a quarter of the mutations belong to connexin genes (GJA3 and GJA8) (6). This evidence concerns the gene GJA3 and early-onset non-syndromic cataract.