Download Document

Epigenetics
What is Epigenetics?
• The study of changes in gene activity that do not
have to do with changes in actual DNA
o Abnormal traits that (as far as we know) are
not necessarily determined in our genes or have no
specific gene but are passed down through at least
one generation
• Often relating to Nature vs. Nurture
What is an Epigenome?
• A large aspect of Epigenetics
o A "switch" that sits on and just outside of a regular
genome
 is responsible for the inheritance of traits caused
by environment
• The codes on Epigenomes tell genes whether to turn on
or off
• Epigenomes determine small things
o Whether we whisper or talk loudly
• Or more important things
o Immunity to disease
o Obesity
o Memory
What is an Epigenome?
• Although the Epigenome can greatly affect normal
genomes, it is not evolution or DNA
• It only adjusts genes, it does not get rid of them or add
new ones
• Just a response to enviornment and fades after a certain
number of generations (But generations can be from 160+)
Effects of Epigenomes
• They are affected by certain life style choices
o Smoking
o Eating habits
• When they are changed, they can cause certain genes to
turn on or be stronger or can cause genes to become
weaker or turn off
o Eating to much might cause genes for obesity to
become stronger while turning genes that control life
expectancy down
Experiment
• Dr. Lars Olov Bygren conducted an experiment where he
collected data from kids born in 1905 who grew up in
Norrbotten, Sweden
o Small farming village
 So small that if harvest was bad people starved
o Harvest was different year to year (to much--too
little)
• Bygren collected data on these kids, their children, and
grandchildren to see what affect this eating pattern
would have on them
Experiment
• Bygren found that kids who had extreme eating habits
had kids and grandchildren who lived shorter lives
o These kids died an average of 32 years before
children who had not experienced this diet
• A separate Experiment where 14,024 pregnant women
from the same area were recruited by ALSPC
(Avon Longitudinal Study of Parents and Children)
• The children and parents have been analyzed since
o Found that specific enviorment conditions in pregnancy
and durring infancy affect children
 Peanut baby oil--peanut allergies
 High anxiety durring pregnancy--baby gets asthma
 Children kept extremely clean--higher risk
of eczema
Experiment
• The experiment also found that 166 fathers in the study
had started smoking before age 11 (right before
the body goes through puberty)
o Sperm could have been effected by epigenomes,
changed by the early smoking
• Sons of the 166 fathers on average had a higher BMI
than other children
Medical Advantages
• Scientist are further researching Epigenetics because, if
they are able to be controlled, it would be helpful in the
medical world
o Trying to develop medicine that is able to turn off a
negative epigenome and turn on a positive one
 2004--the first epigenetic drug was approved
 Azacitidine
 Treats deadly blood tumors/cancers etc.
 Life expectancy is expanded by 9 months+
• Scientists are trying to develop other medicines
that manipulate epigenomes for Cancer, Schizophrenia,
Autism, Alzheimers, Diabetes, etc.
Acknowledgments
• http://www.time.com/time/health/article/0,8599,19519
68-4,00.html
• http://www.pbs.org/wgbh/nova/sciencenow/3411/02.ht
ml