Still not great, but riskier. Found in all animals, not just humans. Caused by mutation in gene that produces pigment. If no pigment is produced, individual has very pale skin, light hair. Average life-span with CF is 30 years.
Water is prevented from passing from bloodstream into lung passages.
Still binds oxygen at normal conc., but at low oxygen conc. Therefore has selective advantage. Tay-Sachs 1 in 30 Jews of Russian origin is carrier. BUT if detected early, can control diet, prevent symptoms. No danger after age 9.