Albinism is a genetic disorder characterized by little or no production of melanin pigment, resulting in pale skin, hair and eyes that are prone to sun damage. It occurs when both parents pass on a recessive gene causing a mutation in the tyrosinase enzyme needed to produce melanin. Differences in skin color between populations are an adaptation to varying levels of ultraviolet radiation exposure from the sun in different climates. People near the equator evolved darker skin containing more melanin to protect against strong UV rays, while those in colder climates developed lighter skin with less melanin since UV exposure is lower.

1. Albinism. Some might wonder why this disorder doesn't "phase out" of the gene pool over
time?
Why do people from different parts of the world have different colored skin?
Why do people from the tropics generally have darker skin color that those who live in colder
climates?
Solution
Albinism:It is a complete or partial absence of pigment in skin hair and eyes. it causes skin
cancers and skin burns due to lack of pigmentation and a number of vision defects.albinism also
called achromasia.
GENEPOOL:It occurs due to recessive genes passed from both parents,it is due to absence of
tyrosinase enzyme(it contains copper for the production of melanin).there are other genetic
mutations which are be associated with albinism.
DIFFERENT PARTS OF THE WORLD HAVE DIFFERENT COLOURED SKIN:
People have different coloured skin due to different types of climates in different parts of the
world,people who live in the tropic side have darker skin then people who live in the colder
countries.but the colour of the people is determines by a pigment caled mealanin.people with
dark skin has more melanin, melanin protects the body from harm ful uv radiations.people with
light pigmentation have less melanin.
PEOPLE IN THE TROPICS GENERALLY HAVE DARKER SKIN THEN PEOPLE WHO
LIVE IN COLDER COUNTRIES:
People who live in the tropics are more exposed to harmful uv radiation so the body produce
more melanin to protect the skin from harm ful uv radiations.In colder climates there is no
harmful uv radiations,so the people has light skin colour.