Lactose Intolerance Worksheet

Lactose Intolerance Worksheet Learning Objectives: Following the workshop, participants will be able to:  Define genotype and phenotype of a trait using lactose intolerance as an example.  Explain how most traits, including lactose tolerance, can be influenced by both genetic and non-genetic factors.  Describe one class activity utilizing the lactose intolerance report to teach multifactorial inheritance. Introduction : In addition to the ancestry reports, 23andMe provides reports for three other categories: Carrier Status,* Traits, and Wellness. For this workshop, we will be focusing on the wellness report for lactose intolerance. Lactose Intolerance Dairy products like milk, yogurt, and cheese contain the sugar lactose. An enzyme called lactase breaks down this sugar. If a person doesn’t produce enough lactase, gut bacteria can convert lactose into gas, causing indigestion, known as lactose intolerance. Some people can digest dairy products without a problem, while others experience indigestion after consuming dairy products. These differences are largely due to a person’s lactase enzyme levels. Lactose Intolerance Workshop Part I: Comparing Profiles Complete the table comparing each of the example profiles for their percent predominant ethnicities, in addition to their likely phenotypes, and genotypes for lactose intolerance. Then answer the questions analyzing the data. Profil e Predominant Ethnicities (%) Likely Phenotype Genotype 1 100% European Not Lactose Intolerant AG 2 48.8% European 38.6% East Asian & Native American Lactose Intolerant GG 3 99.9% European Not Lactose Intolerant AG 4 99.4% Middle Eastern & North African Lactose Intolerant GG 5 100% East Asian & Native American Lactose Intolerant GG 6 62.7% Sub-Saharan African 36.1 % Middle Eastern & North African Lactose Intolerant GG 7 91.9% European Not Lactose Intolerant AA 8 99.5% European Lactose Intolerant GG 9 99.7% European Not Lactose Intolerant AA 10 98.9% South Asian Lactose Intolerant GG © 2015 23andMe, Inc. All Rights Reserved

11 73.6% European 14.1% East Asian & Native American Not Lactose Intolerant AG 12 83.1% Middle Eastern & North African Lactose Intolerant GG 1. What is/are the possible genotype(s) for someone who is likely lactose intolerant? 2. For the same marker, what is/are the possible genotype(s) for someone who likely tolerates lactose? 3. Describe any correlations you may see in the example profiles ethnicity and their ability to tolerate lactose. Lactose Intolerance Workshop Part II: Comparing Profiles Read through the handout on lactose intolerance. Answer the questions as you go. 1. Why is it important that human babies make lactase? 2. Describe the genetic basis for why a person’s LCT gene could stop producing lactase. 3. Jane has East Asian ancestry and often enjoys a glass of milk with her dinner. She has never experienced any symptoms of lactose intolerance. What is her likely phenotype and genotype? Explain. 4. Describe how different ethnicities generally respond to tolerating lactose. How does this compare to the correlations noted in your answer to question 3 in Part I of the lactose intolerance workshop? © 2015 23andMe, Inc. All Rights Reserved