Humans and other animals have many phenotypic variations in eye color. The genetics of eye color are complicated, and color is determined by multiple genes. So far, as many as 15 genes have been associated with eye color inheritance. Some of the eye-color genes include OCA2 and HERC2.
Answers (2). green. There are many reasons accounting for the fact that your eyes go out of focus and it is quite normal in the daily life. The tiredness of eyes can result in your difficulty in focusing on object. A migraine headache, as said by the ophthalmologist, can also cause the eye go out of focus.
Though a lot of people think that twitching eyes are caused by stress or fatigue, the real hidden cause is dry eyes. When eyes are too dry, you involuntarily start blinking to keep them moisturized. After a while, the blinking triggers your nerves and tricks the brain into making your eyes twitch even more.