Associate Professor of Ophthalmic Sciences (in Opt
Columbia University?Medical Center
United States of America
The main focus of Dr. Tkatchenko’s research is identification and characterization of genes and genetic networks underlying refractive eye development, as well as studies of genetic variations causing development of refractive errors. Postnatal refractive eye development is a tightly coordinated process whereby visual input drives ocular growth toward zero refractive error in a process called “emmetropization”. The emmetropization process is regulated by a vision-driven feedback loop in the retina and downstream signaling cascades in other ocular tissues, resulting in correct focal length of the eye (emmetropia). Failure of emmetropization leads to the development of refractive errors, i.e., farsightedness (hyperopia) or nearsightedness (myopia). The prevalence of myopia (the most clinically important refractive error in the human population) has increased from 25% to 44% of the adult population in the United States in the last 30 years, and reached >80% in some parts of Asia. Epidemiological data suggest that low-grade common myopia represents a major risk factor for a number of serious ocular pathologies such as cataract, glaucoma, retinal detachment, and myopic maculopathy, which is comparable to the risks associated with hypertension for stroke and myocardial infarction, and represents the seventh leading cause of blindness. In the U.S., the increasing prevalence of myopia also costs $8.1 billion a year for refractive correction alone, negatively affects self-perception, job and activity choices. It is estimated that 2.5 billion people (1/3 of the world’s population) will be affected by myopia by 2020. Uncorrected refractive errors are the major cause of vision loss (particularly in developing countries) and refractive errors are one of five priority pathological conditions according to the World Health Organization. Environmental factors, such as nearwork and reading, play important role in the development of common myopia; however, recent human genetic studies and gene expression profiling in animal models of myopia revealed that refractive eye development and myopia are controlled by hundreds of genes and complex genetic networks, which account for more than 70% of variance in refraction. Dr. Tkatchenko recently developed a mouse model of myopia and demonstrated that mice undergo emmetropization. He also demonstrated that refractive eye development and myopia in the mouse are fundamentally similar to those in other mammals, including humans. Dr. Tkatchenko’s laboratory is using classical mouse genetics, gene-targeted mouse models, and advanced systems genetics approaches to study genes and genetic networks underlying refractive eye development and myopia.