1. Genes and Type 2 Diabetes

2. • if either parent has the condition, the risk of
developing it is 15 %
• if both parents have the condition, the risk
of developing it is 75 %
• if a non-identical twin has the condition, the
risk of developing it is 10%
• if an identical twin has the condition, the
risk of developing it is 90 %

3. Genes found to be involved so far……..
 A defective lipoprotein lipase (LpL) gene may pose a risk for
coronary artery disease and type 2 diabetes in people who have it.
 Variations in a gene that regulates a protein called calpain-10 is
proving to affect insulin secretion and action and may play a role in
diabetes type 2.
 Defective genes that regulate a molecule called peroxisome
proliferator-activated receptor (PPAR) gamma may contribute to
both type 2 diabetes and high blood pressure in some patients.
 A defective gene has been detected that affects beta3-adrenergic
receptor, which is found in visceral fat cells (those occurring around
the abdominal region). The result is a slow-down in metabolism and
an increase in obesity.
 Defective fatty-acid binding protein 2 (FABP2) gene results in higher
levels of unhealthy fat molecules (particularly triglycerides) – link
between insulin and obesity

4. Thrifty gene
 A theory that some cases of type 2 diabetes and obesity are derived from
normal genetic actions that were once important for survival.
 Existence of a so-called "thrifty" gene, which regulates hormonal
fluctuations to accommodate seasonal changes.
 In certain nomadic populations, hormones are released during seasons
when food supplies have traditionally been low, which results in
resistance to insulin and efficient fat storage.
 The process is reversed in seasons when food is readily available.
 high-carbohydrate and fatty foods available all year long, the gene no
longer serves a useful function and is now harmful because fat, originally
stored for famine situations, is not used up.

6. Ongoing……..
 “Doctors are closer to building a DNA profile of
people who are at risk from diabetes after
pinpointing another set of genes associated with the
disease,” reported The Daily Telegraph.
 On the same page “effective genetic screening is still
someway off”

7. Genes + Environment
 Environmental factors also important
 Adoption of the type 2 diabetes epidemiological
pattern in those who have moved to a different
environment as compared to the same genetic pool
who have not e.g immigrants to Western developed
countries

8. How does Genes + environment work
 Gene expression promoted by a diet of fat and
glucose as well as high levels of inflammation related
cytokines found in the obese
 Results in cells that "produce fewer and smaller
mitochondria than is normal," and are thus prone to
insulin resistance

9. Summary
 Undeniable link.
 Not sole cause – role of environmental factors.
 Several symptoms/signs of diabetes can be linked
back to genes