The murine cataractogenic mutation, Cat Fraser, segregates independently of the gamma crystallin genes

Abstract

The murine mutation, Cat Fraser (Cat(Fr)), causes dominantly inherited ocular cataracts. Lenses of adult mice bearing this mutation contain reduced amounts of all seven γ-crystallin proteins and their corresponding transcripts. Levels of other lens proteins and transcripts appear normal and no extra-ocular effects of the mutation have been observed. The selective effect of this mutation on the γ-crystallins is consistent with the possibility that the site at which it occurs is involved in the coordinated regulation of the family of genes which encodes them. We have shown that several restriction fragment length polymorphisms in the γ-crystallin genes segregate independently of the Cat(Fr) mutation. Therefore, despite its selective effect on the expression of the γ-crystallin genes, the mutation is not linked to them. This observation rules out the possibility that the mutation is in a cis-acting regulatory site.