The Biology of Congenital Color Defects

Protanopia, deuteranopia, protanomaly, and deuter-anomaly all arise from changes in the X chromosome opsin genes. As noted previously, unequal recombination events that occur during meiosis can lead to additions and losses of genes from the X chromosome as well as to the production of novel genes (Fig. 5). Thus, a loss of the L cone opsin produces a protanopic dichromacy; loss of the M opsin yields deuteranopia. On the other hand, the anomalous trichromacies reflect the genomic presence of atypical opsin genes. In these cases, a new pigment replaces either the normal M pigment (in cases of deuteranomaly) or the normal L pigment (in protanomaly). The spectrum of

Anxiety and Depression 101

Anxiety and Depression 101

Everything you ever wanted to know about. We have been discussing depression and anxiety and how different information that is out on the market only seems to target one particular cure for these two common conditions that seem to walk hand in hand.

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