GENES AND VISUAL PIGMENTS OF RED GREEN COLOR VISION

这项研究的长期目标是了解分子 基于锥形感光颜料的视觉遗传学。为了实现这一目标，我们 必须首先建立色觉表型和颜色表型之间的关系 基因分型。这需要对该基因有清晰、准确的了解。 最近的证据表明，底层数组的结构 正常的色觉与之前所认识到的完全不同。 因此，这里提出的工作的直接目标是获得理解 X连锁色素基因阵列的结构。号码是多少？ 以及单个阵列中色素基因的比例，这些数字是如何变化的， 另外，“额外的”色素基因在正常视力和 视力异常？重组机制在什么机制中发挥作用 更改数组的结构；哪些更改与 色觉缺陷和更严重的视力障碍？个人情况如何？ 与色素功能相关的视蛋白氨基酸的差异； 哪些变化与色觉缺陷或其他视觉有关 精神障碍？ 该提案的每个具体目标都建立在不同的新基础上 来自我们实验室的发现。每一项发现都具有深远的影响 对理解基于这些基因的视觉的影响。1)我们有 一些个体没有完整的中波基因的证据，但 相反，它们拥有不完整的基因。2)我们有证据表明个人 构成正常颜色的基因数量和比例的差异 远见比想象的要大得多。3)我们确定了 与原发色觉相关的基因突变 改变了色素的吸收峰，但改变了色素的功能 产生反常三色和二色之间的区别。 为了探索这些发现的影响， 我们的研究是：1)研究X-基因重排。 与视觉色素基因连锁有关的发生频率 正常视力和视力缺陷的不完整中波或长波基因， 以及产生缺失的遗传机制。2)刻画 X连锁视色素基因芯片的基本结构 长波和中波基因在阵列中的数量和比例 色觉正常的观察者和色觉缺陷者。3) 为了表征色觉缺陷下的颜料， 原视和原视，关于光谱敏感性，光学 密度，以及漂白和再生动力学，并探索 基因序列差异与这些功能的关系 编码色素的差异。 色觉正常和有缺陷的男性的视觉能力将 使用心理物理方法和视网膜电信号进行详细检查。 X连锁的色素基因将用Southern分析进行研究， 聚合酶链式反应、DNA序列分析。

The long term goal of this research is to understand the molecular genetics of vision based on cone photopigments. To achieve this goal, we must first establish a relationship between color vision phenotype and genotype. This requires a clear, accurate understanding of the genotype. Recent evidence indicates that the structure of the arrays underlying normal color vision are radically different than previously appreciated. Thus, the immediate goal of the work proposed here is to gain understanding of the structure of the X-linked pigment gene array. What are the numbers and rations of pigment genes in individual arrays, how do the numbers vary, and what role do "extra" pigment genes in play in normal vision and in vision abnormalities? What recombination mechanisms play a role in altering the structure of the array; which alterations are associated with color vision defects and more serious vision disorders? How are individual differences in the amino acids of the opsins related to pigment function; what changes are associated with color vision defects, or other vision disorders? Each of the specific aims of this proposal builds on a different new discovery from our laboratories. Each discovery has far reaching implications for understanding vision based on these genes. 1) We have evidence that some individuals do not have intact middle-wave genes, but instead have incomplete genes. 2) We have evidence that individual differences in the numbers and ratios of genes that underlie normal color vision are far greater than had been imagined. 3) We identified a mutation in the genes underlying protanomalous color vision that does not change the absorption peak of the pigment, yet it alters pigment function to produce the difference between anomalous trichromacy and dichromacy. Toward exploring the implications of these findings the specific aims of our research are: 1) To investigate gene rearrangements among the X- linked visual pigment genes with regard to the frequency of occurrence of incomplete middle- or long-wave genes in normal vision and vision defects, and the genetic mechanisms that produce the deletions. 2) To characterize the basic structure of the X-linked visual pigment gene array with regard tot he number and ration of long- and middle-wave genes in the arrays of observers with normal color vision and those with color vision defects. 3) To characterize athe pigments underlying the color vision defects, protanopia and protanomaly, with regard to spectral sensitivity, optical density, and bleaching and regeneration kinetics, and to explore the relationship between gene sequence differences and these functional differences in encoded pigments. Visual capacities of males with normal and defective color vision will be examined in detail using psychophysical methods and the electroretinogram. The X-linked pigment genes will be investigated using Southern analysis, the polymerase chain reaction,a nd DNA sequence analysis.