Mutations provide important structure–function relationships by allowing the correlation of phenotypes to the underlying genotypes. Knockout mutations that lead to loss-of-function are important and informative in this respect. However, spontaneous and induced mutations sometimes provide surprising phenotypes, which lead to unexpected functional insights and novel biochemical pathways, especially when multiple mutations(alleles) exist at a locus. An excellent example is provided by the microphthalmia (Mitf) locus in the mouse.The multiple Mitf alleles have their own phenotypic properties, most of which have been explained by the underlying mutation. However, one allele, the Mitf (Mi-White) (Mitf (Mi-Wh)) mutation, exhibits phenotypes that have not yet been fully explained. Here, the molecular, genetic, and phenotypic properties of this mutation are reviewed and an attempt made to explain the underlying biochemical reason for its observed effects.

中文翻译：

---

复杂表型的解释：Mitf基因的教训。

突变通过允许表型与基础基因型的相关性提供重要的结构-功能关系。在这方面，导致功能丧失的基因敲除突变很重要，也提供了很多信息。但是，自发突变和诱导突变有时会提供令人惊讶的表型，这会带来意想不到的功能见解和新颖的生化途径，尤其是当一个位点存在多个突变（等位基因）时。小鼠的微眼（Mitf）基因座就是一个很好的例子。多个Mitf等位基因具有自己的表型特性，其中大部分已被潜在的突变所解释。但是，一个等位基因，Mitf（Mi-White）（Mitf（Mi-Wh））突变，表现出尚未完全解释的表型。在这里，分子，遗传，