IS THERE A BIOLOGICAL/ GENETIC BASIS FOR RACE?
*Race has no biological or genetic basis; it is a “social construct” - Genes are responsible for facial
features and skin color, but there is no one characteristic trait/gene that distinguishes all members of one
“race” from all members of another “race”.
*Humans are 99.9% identical genetically. The .1% that does vary is important in determining our
unique selves, but not enough to separate humans into distinct biological/genetic groups. Of this small
amount of human genetic variation that does exist, 85% exists within any local population (Italians,
Nigerians, Swedes, Koreans…). Two random Koreans are likely to be as genetically different as a Korean
and a Nigerian. 90 % of human genetic variation exists between populations from the same continent -->
there is only a 10% genetic difference between populations from different continents So, if there is no
biological basis for race, what best explains human variations in certain populations? geographical
origins! Human genetic variation tends to be “geographically structured”. Because of a history of
extensive migration, intermating and gene flow, human genetic variation is usually distributed in a
continuous fashion (clines) --> Populations are never “pure” in a genetic sense.
(http://www.pbs.org/race/000_General/000_00-Home.htm)
Certain forms (alleles) of some genes are more common (have a higher frequency) in certain parts of the
world, often due to geography/environmental influences and/or where that mutation/variation originated.
Ex, 1. Skin color / UV radiation / Vit D synthesis(needed for Ca absorption) / Folic Acid(needed for
DNA production in dividing cells, normal fetal development): People in the tropics survived better with
dark skin to block out the sun and protect their body's folic acid reserves. People far from the equator
survived better with fair skin to absorb the sun and produce adequate amounts of vitamin D during the
long winter months; 2. sickle cell anemia more common in people of African, Mediterranean and SE
Asian ancestry because “carriers” of the trait are unaffected but have greater resistance to malaria, which
is very common in those parts of the world. (http://anthro.palomar.edu/adapt/adapt_4.htm)
The more recently evolved superficial traits / phenotypes (skin color; eye, hair, lip and nose shape),
that are adaptations to climate are not linked with older, more complex traits, like intelligence,
personality, athletic ability, etc. These superficial traits are characteristic of people whose ancestors are
from certain parts of the world because it is these surface characteristics that interact most directly with
the environment. They generally have to do with the body’s need to regulate temperature. For example,
tightly curled hair allows sweat to stay on the scalp longer and increase evaporative cooling in hotter
climates. In cooler climates, the nose is smaller to prevent heat loss. Almond shaped eyes have extra skin
to protect against cold air. Interbreeding between groups from different parts of the world throughout
human history has resulted in the great diversity of each of these traits that is visible in humans today.
Resources:
1. http://www.racesci.org/index.html 2. http://www.understandingrace.org 3. http://www.newsreel.org/nav/title.asp?tc=CN0149-1.
4. http://www.pbs.org/race/000_General/000_00-Home.htm
5. http://www.raceandhistory.com/historicalviews/rgh.htm