The genetics underlying the fruit colour variation in tomato is an interesting area of both basic and applied research in plant biology. There are several factors, like phytohormones, environmental signals and epistatic interactions between genes, which modulate the ripe fruit colour in tomato. However, three aspects: genetic regulation of skin pigmentation, carotenoid biosynthesis and ripening-associated chlorophyll degradation in tomato fruits are of pivotal importance. Different genes along with their mutant alleles governing the aforementioned characters have been characterized in detail. Moreover, the interaction of these mutant alleles has been explored, which has paved the way for developing novel tomato genotypes with unique fruit colour and beneficial phytonutrient composition. In this article, we review the genes and the corresponding mutant alleles underlying the variation in tomato skin pigmentation, carotenoid biosynthesis and ripening-associated chlorophyll degradation. The possibility of generating novel fruit colour-variants using different combinations of these mutant alleles is documented. Furthermore, the involvement of some other mutant alleles (like those governing purple fruit colour and high fruit pigmentation), not belonging to the aforementioned three categories, are discussed in brief. The simplified representation of the assembled information in this article should not only help a broad range of readers in their basic understanding of this complex phenomenon but also trigger them for further exploration of the same. The article would be useful for genetic characterization of fruit colour-variants and molecular breeding for fruit colour improvement in tomato using the well-characterized mutant alleles.

番茄果实颜色变化的遗传学是植物生物学基础研究和应用研究中一个有趣的领域。有多种因素，例如植物激素，环境信号和基因之间的上位相互作用，这些因素可调节番茄的成熟果实颜色。但是，三个方面：番茄果实的皮肤色素沉着的遗传调控，类胡萝卜素的生物合成和与成熟相关的叶绿素降解至关重要。已经详细表征了不同基因及其支配上述特征的突变等位基因。此外，已经探索了这些突变等位基因的相互作用，这为开发具有独特果实颜色和有益植物营养成分的新型番茄基因型铺平了道路。在这篇文章中，我们审查了番茄皮肤色素沉着，类胡萝卜素的生物合成和与成熟相关的叶绿素降解的变异所涉及的基因和相应的突变等位基因。记录了使用这些突变等位基因的不同组合产生新颖的水果颜色变体的可能性。此外，还简要讨论了不属于上述三类的其他一些突变等位基因（如控制紫色水果颜色和高水果色素沉着的那些）。本文中汇编信息的简化表示，不仅应帮助广泛的读者对这种复杂现象有基本的了解，还应促使他们进一步探索该现象。