METHYL MADNESS!

LEVEL 1 - BASIC FACTS0.5 points per question (write +0.5 next to each one they have correct)

1. D - Obesity• The entire first 2 pages talk about obesity…

2. C

3. B“Their genes were the same as their parents’. The agouti gene in the thin brown mice was right where it was supposed to be, ready to send out instructions to make them fat and yellow. So what happened? Essentially, one or more of the compounds in the vitamin supplements fed to the expectant mothers reached down into the mouse embryos and flicked the agouti gene into the “off ” position.When the baby mice were born, their DNA still contained the agouti gene, but it wasn’t expressed—chemicals had attached to the gene and suppressed its instructions.”

4. A

“The current focus in human epigenetics is on fetal development. It’s now clear that the first few days after conception—when a mother may not even know she’s pregnant—are even more critical than we’ve understood. That’s when many important genes are switched on or off. And the earlier that epigenetic signals are transmitted, the more significant the potential changes are in the fetus.

(In some ways, the womb may be like a tiny evolutionary laboratory, examining new traits to see whether they’ll help the fetus survive and thrive; if they won’t, the mother miscarries. Researchers have certainly noted that many miscarried fetuses have genetic abnormalities.)”

5. B• “Epigenetic effects influence your phenotype without

changing your genotype”

• It’s changes in gene expression, not the genes themselves

6. A

•Explains why only sons seem to be affected

7. C – Children and Grandchildren

8. C• You will examine this study more in depth for level III in

the packet

9. C – harmful and beneficial • E.g. harmful – causing cancer• Beneficial – preventing obesity related diseases

10. B• Most research has focused on mutations in cancer genes

(you will read about BRCA in Breast Cancer)• Changes in gene expression can have the same effect

11. B

12. A• Epigenetics might help explain this mysterious

phenomenon!

Level II – 1 point each

1. Main thesis = D – environment of the parent matters, not just the genes they contain

2. Summary: A – gene expression changes depending on experience

•The genome is more like a choose your own adventure book – sure the pages are already written, but your choices (and your parents choices) affect which ones get read

Level III• Fat agouti mice with good diets Skinny brown babies• Choline increases mouse memories• Twins don’t get same diseases or finger prints• Vole fur thickness depends on temperature during pregnancy• Daphnia helmet and spines depends on predators seen during pregnancy• Desert locust is born camouflage and lonely or bright and in a group• Lizard tail length depends on whether mother smells a lizard-eating snake• Low-nutrient diet by parents Babies with thrifty metabolisms• Low protein rat mothers High blood pressure• Malnourished sheep Thicker arteries• Father smoking Heavier children• Smoking grandmother Asthmatic grandchildren• Dutch famine Obese children, grandchildren• Rat pups Anxiety• Stressed parents Depression and loss of self-control• Twins One gets cancer, other doesn’t• Smoking/Betel Nuts Cancer• Soy Less obesity in Asian populations??