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What is a famine and how does it affect people?
In addition to higher birth weights, what did scientists observe about "children of the famine" whose mothers had been in early pregnancy during the famine?
They were more likely to have obesity and chronic health problems than their siblings who didn't develop during the famine
What does the IGF2 hormone do?
Promotes fetal growth (makes the baby larger)
Why did the children of the famine make more growth hormone?
Their IGF2 genes were demethylated, so more mRNA was made and therefore more protein was produced.
They had average or above-average birth weights
What does the gene IGF2 do?
The IGF2 gene codes for a hormone called insulin-like growth factor 2
How does methylation affect gene expression? In the diagram, which type of DNA is transcribed and which type is NOT transcribed?
Unmethylated DNA is transcribed. Methylated DNA is not transcribed.
What did researchers notice about the offspring of the "children of the famine?"
The offspring of the children of the famine also had larger birth weights, obesity, and chronic health problems
Why were scientists surprised that some of the babies had average or above-average birth weights?
There was a a famine and their mothers had poor nutrition while they were pregnant
They had different gene expression. The IGF2 gene was turned on or off...
Did the "children of the famine" have more of the growth hormone, or less? Explain why.
The children of the famine had more IGF2 (growth factor) because their genes were not methylated.
No, the differences are caused by differences in gene expression. The amount of protein being made is different, but the hormone itself is the same.