1. By: Mandy Butler, Ying-Tsu Loh and Cheryl Ann Peterson
SNPing Lactose
By: Mandy Butler, Ying-Tsu Loh and Cheryl Ann Peterson

2. Three college students walk in an
ice-cream bar. One orders a delicious 100% whole milk milkshake, the other two orders a Tofutti strawberry smoothie. Why?

3. LACTOSE (pre-assess student understanding)
Lactose, the primary sugar in milk, is hydrolyzed by an enzyme called lactase.
Virtually all humans are born with ability to utilize lactose but many lose ability to digest lactose by 12 or 13 years old.
In lactose tolerant individuals, lactase gene is expressed into adulthood, so eating a milkshake is a pleasant experience. But in people who are lactose intolerant, that lactase gene is switched off after weaning, and the consumption of milk products can lead to unpleasant effects.

4. Pre-assess students on SNPs
Scientists found a SNP in gene in the Finnish that seems to be correlated with lactose tolerance.

5. Examine phenotype vs genotype to find any correlation
Which variant(s) are correlated with lactose tolerance?
What is the dominant phenotype of the Finnish population?

6. What is the percentage of the genotype of the total Finnish population?

7. What is your conclusion from looking at the tables?

8. How could a SNP change the phenotype of an individual?
Obtain some hypotheses or conclusions

9. Allele Frequencies from NCBI

10. ALlele FREquency Database   

11. Go to HAPMAP / ALFRED to examine non-Finnish populations
Link to articles or have students find articles associated with the study.
Examine DATA set
Go to HAPMAP / ALFRED to examine non-Finnish populations
What is the genotype frequency at this locus
Are these populations lactose tolerant

12. LAB
Generate primers – have students BLAST the primers to find the sequence that should be amplified
Enter “WebCutter” (Biology Workbench) to find RE that can cut the sequence
Determine the sizes that are produced in either genotypes
Correlate Genotype with Phenotype