If both beta globin genes code for the sickle protein, the person has sickle cell disease. Sickle cell disease is determined at conception, when a person acquires his/her genes from the parents. Sickle cell disease cannot be caught, acquired, or otherwise transmitted.
For every year of the cat's life after age 2, one cat year equals approximately 4 human years. This is based on how cats mature - for example at around 10 - 11 human years most cats start to slow down quite a lot... This is when they're getting to about 60 years old in Kitty terms.
Cat Age Calculator. You'll notice on the cat age calculator above, the biggest differences between the rates at which cats age compared to humans is over the first 2 years of the cat's life. A cat at one year of age is thought to be about 15 in human terms, as cats reach full sexual maturity at one year, whereas humans reach it at about age 15. At 2 years old, cats are thought to be fully grown and completely mature - the equivalent of a human in their early to mid 20s.